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
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
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
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
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
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 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
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
Which of the following correctly describes variable hoisting with 'let' and 'const'?
A). Both 'let' and 'const' declarations are not hoisted
B). Only 'let' declarations are hoisted
C). Only 'const' declarations are hoisted
D). Both 'let' and 'const' declarations are hoisted but not initialized