Assertion :- Flagellates are free-living or parasitic or commensel in nature.
Reason :- Members are most primitive among animals.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

To solve the question regarding the assertion and reason, we will break it down step by step.

### Step 1: Analyze the Assertion
The assertion states that "Flagellates are free-living, parasitic, or commensal in nature."
- This statement is true. Flagellates, which are a group of protozoans characterized by the presence of flagella, can indeed be found living freely in the environment, as parasites in hosts, or in a commensal relationship with other organisms.

### Step 2: Analyze the Reason
The reason states that "Members are most primitive among animals."
- This statement is also true. Flagellates are considered some of the most primitive forms of life in the animal kingdom, as they exhibit simple cellular structures and basic life processes.

### Step 3: Determine the Relationship Between the Assertion and Reason
Now we need to evaluate if the reason provided is a correct explanation for the assertion.
- While both statements are true, the reason does not directly explain why flagellates can be free-living, parasitic, or commensal. The assertion describes the nature of flagellates, while the reason provides information about their evolutionary status.

### Step 4: Choose the Correct Option
Based on the analysis:
- The first option states that both assertion and reason are true, and the reason is the correct explanation of the assertion. This is incorrect.
- The second option states that both assertion and reason are true, but the reason is not a correct explanation of the assertion. This is correct.
- The third option states that the assertion is true but the reason is false. This is incorrect.
- The fourth option states that both assertion and reason are false. This is incorrect.

Thus, the correct answer is **Option 2**: Both assertion and reason are true, but the reason is not a correct explanation of the assertion.

### Summary of Steps
1. Analyze the assertion: True.
2. Analyze the reason: True.
3. Determine the relationship: Reason does not explain the assertion.
4. Choose the correct option: Option 2 is correct.