Can you redeclare a 'let' variable in the same scope in JavaScript?

What will happen if you try to use a variable before declaring it with 'let'?

A). It will return undefined

B). It will return null

C). It will throw a ReferenceError

D). It will return NaN

What happens if you try to redeclare a 'const' variable in JavaScript?

A). It will throw an error

B). The variable is overwritten

C). The variable is converted to 'let'

D). The program continues with a warning

What will be the result of executing 'let x = 1; let x = 2;' in the same scope?

A). x will be 1

B). x will be 2

C). Syntax Error

D). Runtime Error

What error is thrown when attempting to redeclare a 'const' variable?

A). TypeError

B). ReferenceError

C). SyntaxError

D). RangeError

What will happen if you declare a 'let' variable inside a block and try to access it outside the block?

A). It will return undefined

B). It will throw a ReferenceError

C). It will return null

D). It will be accessible outside the block

Which of the following correctly describes variable hoisting with 'var'?

A). 'var' declarations are not hoisted

B). Only the variable declaration is hoisted, not the initialization

C). Both declaration and initialization are hoisted

D). Only in strict mode 'var' declarations are hoisted

Why is it recommended to use 'let' and 'const' over 'var' in modern JavaScript?

A). 'let' and 'const' are function-scoped

B). 'let' and 'const' prevent variable hoisting

C). 'let' and 'const' are block-scoped, reducing potential errors

D). 'let' and 'const' are faster

What happens when you redeclare a variable with 'var' inside a function?

A). The variable is overwritten

B). The variable declaration is ignored

C). It throws an error

D). The function's scope is reset

Can you redeclare a 'var' variable in a different scope without error?

A). Yes

B). No

C). Only in strict mode

D). Only if the variable is not initialized

In which scenario would redeclaring a variable with 'var' lead to an unintended consequence?

A). When redeclaring in the same scope

B). When redeclaring in a different scope

C). When using 'strict mode'

D). When the variable has not been initialized