Showing 471–480 of 654 questions
Read the passage: 'Technology has revolutionized education. Students now have access to online courses from top universities.' What is the main idea?
A
Online courses are free
B
Technology has changed how education is delivered
C
Top universities offer better education
D
All students prefer online learning
Correct Answer:
B. Technology has changed how education is delivered
Explanation:
The passage states that technology has revolutionized education and enabled access to courses. This is the main idea
Which of the following best describes SQL?
A
A programming language for web development
B
A language for managing and querying databases
C
A markup language for creating web pages
D
A platform for cloud computing
Correct Answer:
B. A language for managing and querying databases
Explanation:
SQL (Structured Query Language) is used for managing and querying relational databases
In Java, what does 'final' keyword do when applied to a variable?
A
It makes the variable private
B
It prevents the variable from being modified
C
It makes the variable static
D
It initializes the variable to zero
Correct Answer:
B. It prevents the variable from being modified
Explanation:
'final' keyword makes a variable immutable - once assigned, it cannot be changed
What is the output of: print(10 // 3) in Python?
Explanation:
The '//' operator performs floor division, which returns 3 (the integer part of 10/3)
Which data structure uses LIFO (Last-In-First-Out)?
A
Queue
B
Stack
C
Array
D
Linked List
Explanation:
A Stack uses LIFO principle where the last element added is the first one to be removed
What is the purpose of an index in a database?
A
To store backup data
B
To speed up query retrieval
C
To encrypt sensitive data
D
To remove duplicate records
Correct Answer:
B. To speed up query retrieval
Explanation:
An index is a database structure that improves the speed of data retrieval by creating a quick lookup mechanism
Which protocol is used for secure web communication?
A
HTTP
B
FTP
C
HTTPS
D
SMTP
Explanation:
HTTPS is HTTP with encryption/security using SSL/TLS protocols for secure communication
What is the main purpose of version control systems like Git?
A
To compress files
B
To track changes in code and enable collaboration
C
To encrypt code
D
To execute code
Correct Answer:
B. To track changes in code and enable collaboration
Explanation:
Version control systems track code changes over time and facilitate team collaboration by managing different versions
What is polymorphism in OOP?
A
Using multiple classes in one program
B
The ability of objects to take multiple forms
C
Creating multiple instances of the same class
D
Inheriting from multiple parent classes
Correct Answer:
B. The ability of objects to take multiple forms
Explanation:
Polymorphism allows objects to take multiple forms - same method name can behave differently in different contexts (method overriding, overloading)
Which of the following is NOT a characteristic of Cloud Computing?
A
On-demand self-service
B
Broad network access
C
Physical hardware always on-premises
D
Rapid elasticity
Correct Answer:
C. Physical hardware always on-premises
Explanation:
Cloud computing is characterized by remote resources, not physical hardware on-premises. All others are cloud characteristics
