What is the primary advantage of using block scope in JavaScript?
A). Reducing code size
B). Preventing variable hoisting
C). Avoiding global variables
D). Improving performance
What will be the output of the code above?
A). 30
B). 31
C). TypeError
D). Undefined
Which of the following statements is true about constants declared using const?
A). They can be reassigned multiple times
B). They are hoisted to the top
C). They are mutable
D). They are immutable
What will happen when you try to execute this code?
A). 14 will be logged to the console
B). 14159 will be logged to the console
C). SyntaxError will occur
D). TypeError will occur
What will be logged to the console after executing the code above?
A). ['red', 'blue', 'green', 'yellow']
B). ['red', 'blue', 'green']
C). ['yellow']
D). Error
Which of the following best describes the behavior of JavaScript's const keyword?
A). It prevents variables from being redeclared
B). It ensures variables cannot be reassigned
C). It provides global scope for variables
D). It allows variables to change their data type
What is the benefit of using const over var in JavaScript?
A). const variables have function scope
B). const variables are hoisted to the top
C). const variables prevent accidental reassignments
D). const variables can be used anywhere
What happens if you try to reassign a value to a constant declared using const?
A). SyntaxError
B). TypeError
C). ReferenceError
D). No error, value is reassigned
What does the const keyword signify in JavaScript?
A). Constant variable
B). Mutable variable
C). Global variable
D). Block-scoped variable
In JavaScript, const variables are not hoiste What does this mean?
A). They are hoisted to the top of the block
B). They cannot be used before declaration
C). They are accessible in nested scopes
D). They are block-scoped variables