Haryana Board (HBSE) Class 12 Computer Science Pre Board Question Paper 2024 Answer Key. Haryana Board Class 12th Pre Board Question Paper PDF Download 2024. Haryana Board Class 12th Pre Board Question Paper Computer Science 2024. HBSE Class 12th Computer Science Pre Board Question Paper Solution 2024. HBSE Computer Science Pre Board Question Paper 2024 Class 12.
HBSE Class 12 Computer Science Pre-Board Question Paper 2024 Answer Key
Section – A (1 Mark)
1. (i) Full form of FTP :
(a) Full Transport Protocol
(b) File Transfer Protocol
(c) File Transport Protocol
(d) Fibre Transfer Protocol
Answer – (b) File Transfer Protocol
(ii) …………….. is a collection of related records.
(a) Table
(b) Data Item
(c) File
(d) None of the Above
Answer – (c) File
(iii) Among the following, which is the HTML paragraph tag?
(a) <p>
(b) <pre>
(c) <hr>
(d) <a>
Answer – (a) <p>
(iv) A queue follows …………..
(a) FIFO (First In First Out) principle
(b) LIFO (Last In First Out) principle
(c) Ordered array
(d) Linear tree
Answer – (a) FIFO (First In First Out) principle
(v) In HTML we have …………… heading tags for writing heading?
Answer – Six (<h1> to <h6>)
(vi) The ability of anything to be in different forms at different places is called ………………
Answer – Polymorphism
(vii) “destructor” can be overloaded in C++. (True / False)
Answer – False
(viii) HTML files are saved by default with “.html” extension. (True / False)
Answer – True
(ix) Assertion (A) : Primary key is a set of one or more attributes that identify tuples in a relation uniquely.
Reason (R) : Every table must have one primary key.
(a) Both Assertion and Reason are true and Reason is correct explanation of Assertion.
(b) Both Assertion and Reason are true and Reason is not the correct explanation of Assertion.
(c) Assertion is true but Reason is false.
(d) Assertion is false but Reason is true.
Answer – (a) Both Assertion and Reason are true and Reason is correct explanation of Assertion.
(x) Assertion (A) : The personal area network is established with in a very small area (20 to 30 sq feet) to share the information.
Reason (R) : The campus are network is used to interconnect the computers located within campus such as university campus, corporate campus, hospital campus.
(a) Both Assertion and Reason are true and Reason is correct explanation of Assertion.
(b) Both Assertion and Reason are true and Reason is not the correct explanation of Assertion.
(c) Assertion is true but Reason is false.
(d) Assertion is false but Reason is true.
Answer – (b) Both Assertion and Reason are true and Reason is not the correct explanation of Assertion.
Section – B (1 Mark)
2. Define friend function in C++.
Answer – In C++, a friend function is a function that is not a member of a class but has access to the class’s private and protected members. It is declared inside the class with the `friend` keyword, allowing it to access the private and protected members of the class as if it were a member function.
3. What is Internet?
Answer – The internet is a global network of interconnected computers and devices that communicate with each other using standardized protocols. It allows for the exchange of data and information across vast distances, enabling services such as email, web browsing, file sharing, and online communication.
4. Define 2NF.
Answer – Second Normal Form (2NF) is a database normalization process used to reduce redundancy and improve data integrity. A relation is in 2NF if it is in 1NF and every non-prime attribute is fully functionally dependent on the primary key. In simpler terms, 2NF ensures that each non-key attribute is fully dependent on the entire primary key, rather than just a part of it.
5. What do you mean by DBMS?
Answer – DBMS stands for Database Management System. It is a software system that facilitates the creation, organization, management, and manipulation of databases. DBMS provides users and applications with an interface to interact with the database, allowing them to store, retrieve, update, and delete data efficiently while ensuring data integrity, security, and concurrency control.
Section – C (2 Marks)
6. What is a constructor? Name different types of constructor in C++.
Answer – A constructor in C++ is a special member function of a class that is automatically called when an object of the class is created. Its primary purpose is to initialize the object’s data members.
Different types of constructors in C++ include :
(i) Default Constructor
(ii) Parameterized Constructor
(iii) Copy Constructor
(iv) Move Constructor
7. What do you mean by normalization?
Answer – Normalization is a database design technique used to organize and structure relational databases to reduce redundancy and dependency. The primary goals of normalization are to eliminate data anomalies, improve data integrity, and ensure efficient data storage and retrieval.
8. What is use of <b> and <br> tag in HTML?
Answer – The <b> tag enhances the visual style of text by making it bold, while the <br> tag controls the layout by creating line breaks.
9. Priya is working on her history assignment, digging into research on ancient civilizations. She relies on Mozilla Firefox to search for suitable information.
(Give answer based on the above information)
(i) Mozilla Firefox is an example of a ……………
(a) Website
(b) Web browser
(c) Web Page
(d) None of Above
Answer – (b) Web browser
(ii) Having found valuable information, when Priya clicks on the provided link to access a website, the link is known as a ……………
(a) Domain name
(b) Web Page
(c) URL
(d) IP address
Answer – (c) URL
10. In a company in Mumbai, they use a computer system to keep track of employee information. They have a database called ’employee_database’ with two tables. Employee Table : This table has basic details about each person working in the company.
Issued Tools Table : Here, they store information about tools or equipment given to employees.
Tool ID is like a special number for each tool. And the shortest time a tool can be given to an employee is one day.
(i) The Primary Key for Issued Tools Table Table is/are ……………..
(a) Tool ID
(b) Tool ID, Employee ID
(c) Employee ID, Designation
(d) Department
Answer – (b) Tool ID, Employee ID
(ii) The Alternate Key for Employee Table will be ……………
(a) Employee ID
(b) Designation
(c) Department
(d) None of Above
Answer – (a) Employee ID
Section – D (4 Marks)
11. What is Software Engineering? Explain different phases of SDLC.
Answer – Software Engineering is the application of engineering principles and practices to the design, development, maintenance, testing, and evaluation of software and systems. It encompasses various disciplines such as computer science, project management, and quality assurance to ensure that software products are developed efficiently, reliably, and meet the requirements of stakeholders.
The Software Development Life Cycle (SDLC) is a process used by software development teams to design, develop, test, and deploy software applications. It consists of several phases, each with its specific goals and activities :
(i) Requirements
(ii) Analysis
(iii) Design
(iv) Implementation
(v) Testing
(vi) Deployment
(vii) Maintenance
These phases of the SDLC are often iterative and may overlap, depending on the development approach and project requirements. Effective management and coordination of these phases are essential for delivering high-quality software products on time and within budget.
12. What is a computer network? Why do we need networking in computers? Explain different types of computer networks.
Answer – A computer network is a collection of interconnected devices that can communicate and share resources with each other. We need networking in computers to facilitate communication, resource sharing, and collaboration among devices and users.
There are several types of computer networks :
(i) Local Area Network (LAN) – A LAN connects devices within a limited area, like a home, office, or school campus. It’s typically used for sharing files, printers, and internet access.
(ii) Wide Area Network (WAN) – WAN spans a large geographical area, connecting LANs across cities, countries, or continents. The internet is the largest WAN, enabling global communication.
(iii) Metropolitan Area Network (MAN) – A MAN covers a larger geographical area than a LAN but smaller than a WAN. It connects LANs in a city or metropolitan area.
(iv) Virtual Private Network (VPN) – VPN creates a secure connection over all public network like the internet, allowing users to access a private network remotely. It’s commonly used for remote work and securing sensitive data.
(v) Personal Area Network (PAN) – PAN connects devices in close proximity to an individual, like Bluetooth-enabled devices such as smartphones, tablets, and wearable technology.
Each type of network serves different purposes and comes with its own advantages and limitations, depending on factors like distance, speed, security requirements, and the number of devices to be connected.
13. Explain each :
(i) Internet
Answer – The internet is a global network of interconnected computers and devices that communicate with each other using standardized protocols. It allows for the exchange of data and information across vast distances, enabling services such as email, web browsing, file sharing, and online communication.
(ii) SMTP
Answer – SMTP stands for Simple Mail Transfer Protocol. It’s a standard protocol used for sending emails across the internet. Essentially, SMTP governs how emails are sent from a client (like your email application) to a server, and then between servers until they reach their destination. It works in conjunction with other protocols like POP3 or IMAP, which handle the receiving of emails.
(iii) www
Answer – ‘www’ stands for World Wide Web. It’s a system of interlinked hypertext documents accessed via the Internet. Essentially, it’s what most people think of as the “web” or the “internet” – a vast network of websites, webpages, and multimedia content that you can access using a web browser. The WWW was invented by Tim Berners-Lee in 1989 and has since become a fundamental part of how we share and access information online.
(iv) Firewall
Answer – A Firewall is a network security device that monitors and filters incoming and outgoing network traffic based on an organization’s previously established security policies. At its most basic, a firewall is essentially the barrier that sits between a private internal network and the public Internet. A firewall’s main purpose is to allow non-threatening traffic in and to keep dangerous traffic out.
14. Define Constructor in C++. Explain different types of constructors.
Answer – A constructor in C++ is a special member function of a class that is automatically called when an object of the class is created. Its main purpose is to initialize the object’s data members. Constructors have the same name as the class and do not have a return type, not even ‘void’.
Types of Constructors in C++ :
(i) Default Constructor – A default constructor is a constructor that takes no arguments. If no constructor is defined, the compiler provides a default constructor. Used to initialize members with default values.
(ii) Parameterized Constructor – A parameterized constructor is a constructor that takes one or more arguments. Allows initialization of an object with specific values.
(iii) Copy Constructor – A copy constructor is a constructor that initializes an object using another object of the same class. Takes a reference to an object of the same class as an argument.
(iv) Move Constructor – A move constructor transfers resources from a temporary object (rvalue) to a new object. Takes an rvalue reference to an object of the same class as an argument. Useful for optimizing performance by avoiding deep copies.
Constructors are crucial for initializing objects in C++. They come in various forms to handle different initialization scenarios, such as default, parameterized, copy, and move constructors. Each type serves a specific purpose and ensures that objects are properly set up when they are created.