Which statement about JavaScript's const is true?
A). const variables can be redeclared
B). const variables are globally scoped
C). const variables are mutable
D). const variables cannot be reassigned
What happens if you try to declare a const variable without initializing it immediately?
A). SyntaxError
B). ReferenceError
C). TypeError
D). No error, the variable remains undefined
What will be the output of the code above?
A). 30
B). 31
C). Error
D). Undefined
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
Which of the following statements is true about block scope in JavaScript?
A). Variables declared with let have global scope
B). Variables declared with let have function scope
C). Variables declared with let are block-scoped
D). Variables declared with let are hoisted
Which of the following is NOT an example of a block in JavaScript?
A). Function body
B). if statement body
C). while loop body
D). Object literal
What does the const keyword signify in JavaScript?
A). Constant variable
B). Mutable variable
C). Global variable
D). Block-scoped variable
What is the primary distinction between const and let in JavaScript?
A). const variables are immutable
B). let variables are block-scoped
C). const variables have function scope
D). let variables can be reassigned
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
What will be the output of the code above?
A). 30
B). 31
C). TypeError
D). Undefined