Can 'const' be used to declare an array or object?
A). No, only primitives
B). Yes, but the reference can't change
C). Yes, and the content can't change
D). No
What will be the output of the following code: if (true) { let b = 60; } console.log(b);
A). 60
B). undefined
C). Error
D). null
What will be the output of the following code: const z = 30; z = 40; console.log(z);
A). 30
B). 40
C). Error
D). undefined
What is the scope of a variable declared with 'let' inside a loop?
A). Global
B). Function
C). Loop block
D). Entire script
What will be the output of the following code: let c = 70; { let c = 80; console.log(c); } console.log(c);
A). 70 80 80
B). 80 80
C). Error
D). 70 80
What will be the output of the following code: const d = 90; d = 100; console.log(d);
A). 90
B). 100
C). Error
D). undefined
What will happen if you declare a variable without 'var', 'let', or 'const'?
A). Creates a global variable
B). Creates a block-scoped variable
C). Creates a function-scoped variable
D). Throws an error
What is the default scope of variables declared with the 'var' keyword in JavaScript?
A). Block scope
B). Function scope
C). Module scope
D). Block and function scope
What will be the output of the following code: let y = 10; let y = 20; console.log(y);
A). 10
B). 20
C). Error
D). undefined
Can you re-declare a variable using 'const' in the same scope?
A). Yes
B). No
C). Only in functions
D). Only in loops