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'
Which data type represents unique and immutable values in JavaScript introduced in ES6?
A). Symbol
B). Object
C). Array
D). Function
What does NaN represent in JavaScript?
A). Not a Number
B). Infinity
C). Positive Infinity
D). Negative Infinity
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 true in JavaScript?
A). Number
B). String
C). Boolean
D). Undefined
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 outcome of typeof [1, 2, 3] in JavaScript?
A). String
B). Number
C). Array
D). Object
Which of the following is a primitive data type in JavaScript?
A). Object
B). Array
C). Function
D). Boolean
Which data type represents a block of reusable code in JavaScript?
A). String
B). Object
C). Function
D). Number