Which of the following is true about variable naming conventions in JavaScript?
A). Variable names can start with a number
B). Variable names are case-insensitive
C). Variable names can include spaces
D). Variable names are case-sensitive
What will be the output of the following code?
var x = 5; var y = 6; var z = x + y;
A). 11
B). 11
C). 5
D). 6
Which of the following will cause an error?
A). let a = 10; a = 20;
B). const a = 10; a = 20;
C). var a = 10; a = 20;
D). None of the above
What will be the output of the following code?
var a = 1; { var a = 2; } console.log(a);
A). 1
B). 2
C). undefined
D). ReferenceError
What will be the output of the following code?
const a = 10; a = 20; console.log(a);
A). 10
B). 20
C). Error
D). undefined
What will be the output of the following code?
let a = 1; let b = 2; let c = a + b; console.log(c);
A). 12
B). 12
C). 3
D). NaN
What is the correct syntax for declaring a variable in JavaScript?
A). let myVar = 5;
B). myVar let = 5;
C). 5 = let myVar;
D). let = myVar 5;
Which of the following is correct about variable scope in JavaScript?
A). var is block-scoped
B). let is function-scoped
C). const is block-scoped
D). All variables are global
Can you reassign a value to a variable declared with let?
A). Yes
B). No
C). Only in strict mode
D). Only inside a block
What is hoisting in JavaScript?
A). Function call before declaration
B). Variable declared at the top
C). Variable and function declaration are moved to the top
D). Variable scope