How does 'let' differ from 'var' in terms of scope?
A). 'let' is function-scoped, 'var' is block-scoped
B). Both 'let' and 'var' are block-scoped
C). 'let' is block-scoped, 'var' is function-scoped
D). Both 'let' and 'var' are function-scoped
What is the result of redeclaring a variable with 'var' in the same scope in JavaScript?
A). Syntax Error
B). The variable is overwritten
C). The variable remains unchanged
D). The program crashes
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
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 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
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
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
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 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
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