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 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
How can you declare a constant named PI with a value of 3.14 in JavaScript using const?
A). const PI = 3.14;
B). PI = 3.14;
C). let PI = 3.14;
D). var PI = 3.14;
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). Error
D). Undefined
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
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 will be the output of the code above?
A). 10
B). 20
C). Error
D). Undefined
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
What will be the output of the code above?
A). 30
B). 31
C). TypeError
D). Undefined