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

What is the outcome of typeof undefined in JavaScript?

A). String

B). Undefined

C). Null

D). Number

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

A). instanceof

B). typeof

C). isInstanceof

D). isTypeOf

What is the outcome of typeof [1, 2, 3] in JavaScript?

A). String

B). Number

C). Array

D). Object

Which data type represents an intentional absence of any value in JavaScript?

A). Null

B). Undefined

C). String

D). Number

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

A). Array

B). Symbol

C). Map

D). Tuple

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

A). Number

B). String

C). Boolean

D). Undefined

What is the data type of the value 'null' (with quotes) in JavaScript?

A). String

B). Number

C). Null

D). Undefined

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 will the following code snippet output: let a = 10; a += '5'; console.log(a); in JavaScript?

A). '105'

B). 105

C). 15

D). '15'