Assertion: Most probable velocity is the velocity possessed by maximum fraction of molecules at the same temperature.
Reason: On collision, more and more molecules acquire higher speed at the same temperature.

Options

A. If both the statement are TRUE and STATEMENT-2 is the correct explanation of STATEMENT-1
B. If both the statement are TRUE but STATEMENT-2 is NOT the correct explanation of STATEMENT-1
C. If STATEMENT-1 is TRUE and STATEMENT-2 is FALSE
D. If STATEMENT-1 is FALSE and STATEMENT-2 is TRUE

Answer

To solve the question, we need to evaluate the two statements provided: the assertion and the reason.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Most probable velocity is the velocity possessed by maximum fraction of molecules at the same temperature."
- This statement is indeed correct because the most probable velocity is defined as the speed at which the largest number of molecules in a gas sample are moving at a given temperature. It corresponds to the peak of the Maxwell-Boltzmann distribution curve.

2. **Understanding the Reason**:
- The reason states that "On collision, more and more molecules acquire higher speed at the same temperature."
- This statement is incorrect. While collisions can result in some molecules gaining speed, the overall distribution of speeds does not mean that a larger fraction of molecules will have higher speeds. In fact, the fraction of molecules with very high speeds remains small, as indicated by the shape of the Maxwell-Boltzmann distribution.

3. **Analyzing the Statements**:
- Since the assertion is true and the reason is false, we conclude that the overall answer to the question is that the assertion is correct, but the reason is not.

4. **Final Conclusion**:
- The correct answer is that the first statement (assertion) is true, and the second statement (reason) is false.