Can you re-declare a variable using 'const' in the same scope?
A). Yes
B). No
C). Only in functions
D). Only in loops
Which keyword is used for declaring variables that should not change?
A). var
B). let
C). const
D). all of the above
What will be the output of the following code: var e = 110; if (true) { var e = 120; } console.log(e);
A). 110
B). 120
C). Error
D). undefined
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 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 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
Which of the following statements is true about 'const'?
A). It allows re-declaration
B). It allows reassignment
C). It is block-scoped
D). It is function-scoped
How does 'let' differ from 'var' in terms of scope?
A). No difference
B). Function-scoped
C). Block-scoped
D). Global-scoped
Which keyword should be used by default to declare variables in modern JavaScript?
A). var
B). let
C). const
D). Either B or C
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