Which of the following is NOT an example of a block in JavaScript?
A). A. Function body
B). B. if statement body
C). C. while loop body
D). D. Object literal
What will be the output of the code above?
A). A. 30
B). B. 31
C). C. Error
D). D. Undefined
What will be logged to the console?
A). A. 'John'
B). B. 'Jane'
C). C. Error
D). D. Undefined
What will be the output of the code above?
A). A. 10
B). B. 20
C). C. Error
D). D. Undefined
What is the purpose of using block scope in JavaScript?
A). A. To declare constants
B). B. To prevent variable hoisting
C). C. To improve code performance
D). D. To create global variables
What will be the output of the code above?
A). A. [1, 2, 3, 4]
B). B. [1, 2, 3]
C). C. [1, 2, 3, 4, 5]
D). D. Error
Which of the following statements is true about block scope in JavaScript?
A). A. Variables declared with let have global scope
B). B. Variables declared with let have function scope
C). C. Variables declared with let are block-scoped
D). D. Variables declared with let are hoisted
What does the const keyword signify in JavaScript?
A). A. Constant variable
B). B. Mutable variable
C). C. Global variable
D). D. Block-scoped variable
Which statement is true regarding the const keyword in JavaScript?
A). A. Constants declared with const are hoisted
B). B. Constants declared with const can be reassigned
C). C. Constants declared with const have global scope
D). D. Constants declared with const are immutable
How can you declare a constant named PI with a value of 3.14 in JavaScript using const?
A). A. const PI = 3.14;
B). B. PI = 3.14;
C). C. let PI = 3.14;
D). D. var PI = 3.14;