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Q. The snippet that has to be used to check if “a” is not equal to “null” is _________

Explanation by: Admin

In JavaScript, we use !== (strict inequality operator) to check both:

Example: Checking if a is not null

var a = "Hello";  // Example value

if (a !== null) {

    console.log("a is not null");

} else {

    console.log("a is null");

}

Output:

a is not null

If a = null, then the condition fails.

Why Not Other Options?

(B) if(a!null) → ❌ Incorrect (invalid syntax; ! should be used with boolean expressions, not values).
(C) if(!a) → ❌ Incorrect (this checks if a is falsy, but 0, "", undefined, NaN, and false are also falsy, not just null).
(D) if(a != null) → ✅ Correct, but (A) is preferred because != does type coercion, whereas !== strictly checks for null.

Final Answer:

✅ (A) if(a !== null) (Best practice for checking null).

Explanation by: Admin