Assertion (A) : When a dice is thrown the event of getting the first whole number is an impossible event.

Reason (R) : The probability of an event always lies between 0 and 1.

1. Both A and R are correct, and R is the correct explanation for A.

2. Both A and R are correct, and R is not the correct explanation for A.

3. A is true, but R is false.

4. A is false, but R is true.

A standard die has six faces, numbered 1 to 6.

The term "first whole number" typically refers to 0, which is indeed one of the impossible outcomes when a die is thrown.

Therefore, the event of getting the first whole number (i.e., 0) is a impossible event.

So, assertion (A) is true.

For any event A,

0 ≤ P(A) ≤ 1, not 0 < P(A) < 1.

Thus, the probability of an event always lies between 0 and 1, including 0 and 1 as well.

So, reason (R) is false.

∴ A is true, but R is false.

Hence, option 3 is the correct option.