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
What is the outcome of typeof [1, 2, 3] in JavaScript?
A). String
B). Number
C). Array
D). Object
What does NaN represent in JavaScript?
A). Not a Number
B). Infinity
C). Positive Infinity
D). Negative Infinity
Which of the following is a primitive data type in JavaScript?
A). Object
B). Array
C). Function
D). Boolean
What will let x = '10'; let y = x - 5; console.log(y); output in JavaScript?
A). '5'
B). 5
C). '10'
D). 10
What will let x = null; console.log(typeof x); output in JavaScript?
A). Object
B). Null
C). Undefined
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
Which data type represents positive infinity in JavaScript?
A). Infinity
B). Number
C). NaN
D). Null
What is the data type of the value 'null' (with quotes) in JavaScript?
A). String
B). Number
C). Null
D). Undefined