Which data type represents an intentional absence of any value in JavaScript?
A). Null
B). Undefined
C). String
D). Number
Which of these is a complex or reference data type in JavaScript?
A). Number
B). Boolean
C). Object
D). String
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'
Which of the following is not a valid data type in JavaScript?
A). Array
B). Symbol
C). Map
D). Tuple
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 result of 0 / 0 in JavaScript?
A). Infinity
B). 0
C). NaN
D). 1
What is the outcome of typeof [1, 2, 3] in JavaScript?
A). String
B). Number
C). Array
D). Object
Which data type represents unique and immutable values in JavaScript introduced in ES6?
A). Symbol
B). Object
C). Array
D). Function
What is the data type of the value undefined in JavaScript?
A). Number
B). Boolean
C). String
D). Undefined