What happens if you declare a variable without initializing it in JavaScript?

What will be the value of x after the following code executes: let x = '5' + 5;?

A). '55'

B). 10

C). 5

D). '10'

What will be the output of the following code: console.log(typeof 'Hello');?

A). string

B). number

C). undefined

D). boolean

Which variable declaration is appropriate if you want a variable to hold a constant value throughout the program execution?

A). let

B). var

C). const

D). constant

What will be the value of x after the following code executes: let x = 10; x += 5;?

A). 15

B). 5

C). 10

D). undefined

Which symbol is used for string concatenation in JavaScript?

A). +

B). -

C). *

D). /

What is the purpose of the NaN (Not a Number) value in JavaScript?

A). To represent a number that is not a valid JavaScript number

B). To represent a zero value

C). To represent an infinite value

D). To represent an empty string

Which statement correctly assigns the value true to a boolean variable isLogged in JavaScript?

A). let isLogged = 'true';

B). let isLogged = true;

C). let isLogged = 1;

D). let isLogged = 0;

What is the purpose of using the === operator in JavaScript?

A). Strict equality comparison

B). Loose equality comparison

C). Assignment operator

D). Addition operator

What is the scope of a variable declared using the let keyword in JavaScript?

A). Block scope

B). Function scope

C). Global scope

D). Local scope

What is the keyword used to declare variables in JavaScript?

A). let

B). variable

C). var

D). const