What will let x = '10'; let y = x - 5; console.log(y); output in JavaScript?
A). '5'
B). 5
C). '10'
D). 10
What is the data type of the value undefined in JavaScript?
A). Number
B). Boolean
C). String
D). Undefined
What is the data type of the value 42 in JavaScript?
A). String
B). Boolean
C). Number
D). Null
Which data type represents a block of reusable code in JavaScript?
A). String
B). Object
C). Function
D). Number
Which of the following is not a valid data type in JavaScript?
A). Array
B). Symbol
C). Map
D). Tuple
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'
What will be the result of typeof 'hello' in JavaScript?
A). String
B). Number
C). Undefined
D). Function
Which of the following is a primitive data type in JavaScript?
A). Object
B). Array
C). Function
D). Boolean
What is the outcome of typeof undefined in JavaScript?
A). String
B). Undefined
C). Null
D). Number
Which data type represents an intentional absence of any value in JavaScript?
A). Null
B). Undefined
C). String
D). Number