What is the data type of the value undefined in JavaScript?

Which data type represents unique and immutable values in JavaScript introduced in ES6?

A). Symbol

B). Object

C). Array

D). Function

Which data type represents a block of reusable code in JavaScript?

A). String

B). Object

C). Function

D). Number

What is the data type of the value 42 in JavaScript?

A). String

B). Boolean

C). Number

D). Null

Which operator checks if an object is an instance of a specific object type in JavaScript?

A). instanceof

B). typeof

C). isInstanceof

D). isTypeOf

Which data type represents positive infinity in JavaScript?

A). Infinity

B). Number

C). NaN

D). Null

What does NaN represent in JavaScript?

A). Not a Number

B). Infinity

C). Positive Infinity

D). Negative Infinity

What will let x = '10'; let y = x - 5; console.log(y); output in JavaScript?

A). '5'

B). 5

C). '10'

D). 10

Which of these is a complex or reference data type in JavaScript?

A). Number

B). Boolean

C). Object

D). String

What will let x = null; console.log(typeof x); output in JavaScript?

A). Object

B). Null

C). Undefined

D). Number

What is the result of 0 / 0 in JavaScript?

A). Infinity

B). 0

C). NaN

D). 1