Q
How do you declare a variable with an undefined value?

Answer & Solution

Answer: Option A
Solution:
Declaring a variable without assigning a value to it initializes it with undefined.
Related Questions on Average

What will typeof NaN return?

A). number

B). NaN

C). undefined

D). object

What is the result of typeof undefined?

A). undefined

B). null

C). object

D). number

What is the data type of an array in JavaScript?

A). Array

B). Object

C). Collection

D). List

Which of the following is a falsy value in JavaScript?

A). 0

B).

C). null

D). All of the above

Which function can convert a number to a string in JavaScript?

A). toString()

B). parseInt()

C). String()

D). Number()

What is the output of '5' + 3?

A). 8

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C). 8

D). Error

What will typeof [1, 2, 3] return?

A). array

B). object

C). number

D). list

Which of the following is not a primitive data type in JavaScript?

A). String

B). Number

C). Object

D). Boolean

What is the result of null === undefined?

A). 1

B). 0

C). Error

D). NaN

What is the output of typeof function() {}?

A). function

B). object

C). undefined

D). number