What is the outcome of typeof undefined in JavaScript?
A). String
B). Undefined
C). Null
D). Number
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
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 is the data type of the value 'null' (with quotes) in JavaScript?
A). String
B). Number
C). Null
D). Undefined
What will be the result of typeof 'hello' in JavaScript?
A). String
B). Number
C). Undefined
D). Function
What is the data type of the value 42 in JavaScript?
A). String
B). Boolean
C). Number
D). Null
Which data type represents positive infinity in JavaScript?
A). Infinity
B). Number
C). NaN
D). Null
Which data type represents unique and immutable values in JavaScript introduced in ES6?
A). Symbol
B). Object
C). Array
D). Function
What will let x = '10'; let y = x - 5; console.log(y); output in JavaScript?
A). '5'
B). 5
C). '10'
D). 10