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
Which of the following statements about 'let' and 'const' is false?
A). Both 'let' and 'const' are block-scoped
B). Both 'let' and 'const' cannot be redeclared in the same scope
C). 'let' can be reassigned, 'const' cannot
D). Both 'let' and 'const' can be redeclared in different scopes
How does the scope of 'var' differ from 'let' and 'const' inside a function?
A). 'var' is block-scoped, 'let' and 'const' are function-scoped
B). 'var', 'let', and 'const' are all block-scoped
C). 'var' is function-scoped, 'let' and 'const' are block-scoped
D). 'var' and 'let' are block-scoped, 'const' is function-scoped
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 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
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 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
Given 'var a = 1; var a = 2;', what is the value of 'a' after these statements execute?
A). 1
B). 2
C). Undefined
D). Syntax Error
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
Can you redeclare a 'let' variable in the same scope in JavaScript?
A). Yes
B). No
C). Only in strict mode
D). Only in non-strict mode