JavaScript - Quiz | Analytics

Q: What will be the output of the following JavaScript code?


var a = 12;
{
    let a = 65;
    console.log(a);
}

A. 10
B. 65
C. Undefined
D. Error

Correct Option: B
Remarks:

Explanation:

Q: What will be the output of the following JavaScript code?


const a = 11;
const a = 12;

A. 10
B. 12
C. Undefined
D. Error

Correct Option: D
Remarks:

Explanation:


const a = 12;
      ^

SyntaxError: Identifier 'a' has already been declared

Q: What will be the output of the following JavaScript code?

 
let a = 11;
let a = 12;

A. 10
B. 12
C. Undefined
D. Error

Correct Option: D
Remarks:

Explanation:


const a = 12;
      ^

SyntaxError: Identifier 'a' has already been declared

Q: What is the purpose of the JavaScript "null" primitive data type?

A. Represents an undefined value
B. Denotes a deliberate absence of any object value
C. Holds boolean values
D. Stores textual data

Correct Option: B
Remarks:

Explanation:

The "null" primitive data type in JavaScript is used to explicitly indicate the absence of any object value. It is often assigned to variables to represent a deliberate lack of value or the intentional absence of an object.

Q: What does the JavaScript "boolean" primitive data type represent?

A. Textual information
B. Numeric values
C. True or false values
D. Objects and arrays

Correct Option: C
Remarks:

Explanation:

The "boolean" primitive data type in JavaScript is used to represent logical values, specifically true or false. It is essential for making decisions and controlling the flow of a program through conditional statements.

Q: How is the JavaScript "symbol" primitive data type unique?

A. It represents textual information
B. It is immutable and unique
C. It holds numeric values
D. It denotes a deliberate absence of any object value

Correct Option: B
Remarks:

Explanation:

The "symbol" primitive data type in JavaScript is unique and immutable, making each symbol distinct. It is often used for creating unique identifiers in objects and preventing unintended modifications.

Q: All user-defined objects and built-in objects are descendants of an object called Object?

A. true
B. false

Correct Option: A
Remarks:

Explanation: true

Q: Which of the following function of String object causes a string to be displayed in the specified size as if it were in a tag?

A. fixed()
B. fontcolor()
C. fontsize()
D. bold()

Correct Option: C
Remarks:

Explanation: fontsize()

JavaScript - Quiz

Question: What will be the output of the following JavaScript code?

Question: What will be the output of the following JavaScript code?

Question: What will be the output of the following JavaScript code?

Question: What is the purpose of the JavaScript "null" primitive data type?

Question: What does the JavaScript "boolean" primitive data type represent?

Question: How is the JavaScript "symbol" primitive data type unique?

Question: All user-defined objects and built-in objects are descendants of an object called Object?

Question: Which of the following function of String object causes a string to be displayed in the specified size as if it were in a tag?

Question: Which of the following function of Array object applies a function simultaneously against two values of the array (from left-to-right) as to reduce it to a single value?

Question: Which of the following function of Array object represents the source code of an object?

Q: Which of the following function of Array object applies a function simultaneously against two values of the array (from left-to-right) as to reduce it to a single value?

Q: Which of the following function of Array object represents the source code of an object?

JavaScript - Quiz

Question: What will be the output of the following JavaScript code? var a = 12; { let a = 65; console.log(a); }

Question: What will be the output of the following JavaScript code? const a = 11; const a = 12;

Question: What will be the output of the following JavaScript code? let a = 11; let a = 12;

Question: What is the purpose of the JavaScript "null" primitive data type?

Question: What does the JavaScript "boolean" primitive data type represent?

Question: How is the JavaScript "symbol" primitive data type unique?

Question: All user-defined objects and built-in objects are descendants of an object called Object?

Question: Which of the following function of String object causes a string to be displayed in the specified size as if it were in a tag?

Question: Which of the following function of Array object applies a function simultaneously against two values of the array (from left-to-right) as to reduce it to a single value?

Question: Which of the following function of Array object represents the source code of an object?

Question: What will be the output of the following JavaScript code?

Question: What will be the output of the following JavaScript code?

Question: What will be the output of the following JavaScript code?