The let keyword introduced in ES6 is used to declare block-scoped variables, meaning they are limited to the block in which they are defined. The correct option is b. Variables declared with let are block-scoped.
3.
What is the purpose of using the const keyword in JavaScript?
The const keyword in JavaScript is used to declare constants with immutable values, meaning their values cannot be reassigned after initialization. The correct option is c. To declare constants with immutable values.
4.
Which keyword is used to declare a variable that cannot be reassigned in JavaScript?
Variables declared with the const keyword in JavaScript cannot be reassigned a new value after initialization, making them constants. The correct option is c. const.
5.
What will happen if you try to reassign a value to a constant declared with const in JavaScript?
Constants declared with const in JavaScript cannot be reassigned, and attempting to do so will result in an error. The correct option is a. It will throw an error.
6.
Which of the following variable names is valid in JavaScript?
Variable names in JavaScript can contain letters, digits, underscores, and dollar signs, but they cannot start with a digit. The correct option is b. _variable.
7.
What is the outcome of console.log(typeof x); if x is declared but not initialized in JavaScript?
Hoisting in JavaScript refers to the behavior of moving variable declarations to the top of their scope during compilation. The correct option is c. Moving variable declarations to the top.
9.
What is the difference between var and let in terms of scope in JavaScript?
Variables declared with var have function scope, meaning they are scoped to the nearest function block, while variables declared with let have block scope, limited to the block they are defined in. The correct option is c. varhas block scope,let has function scope.
10.
20 MCQ on Declaring (Creating) JavaScript Variables in 2000 words with example. in excel format with Question in Col A, Option A in Col B, Option B in col C, Option C in col D, Option D in col e, Right Answer in col f, Solution with explanation in col g without sno and options a,b,c,d and put all html tags in special container