Assertion: The head of cockroach is hypognathus.
Reason: The proximal part of lower lip of cockroach is called pastmentum.

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
B. If both Assertion and Reason are true, but the Reason is not the correct explanation of the Assertion.
C. If Assertion is true, but Reason is false.
D. If both Assertion and Reason are false.

Answer

To analyze the given assertion and reason, we can break down the solution into the following steps:

### Step 1: Understand the Assertion
The assertion states that "The head of cockroach is hypognathus."
- **Hypognathous** means that the head is oriented such that the mouthparts are directed downwards. In cockroaches, the head is indeed hypognathous, which allows them to feed on various substrates.

### Step 2: Understand the Reason
The reason states that "The proximal part of the lower lip of cockroach is called pastmentum."
- The lower lip of the cockroach is known as the **labium**, and it has a part called the **palp**. The term "pastmentum" refers to the proximal part of the labium, which is indeed correct.

### Step 3: Evaluate the Relationship
Now we need to determine if the reason provided justifies the assertion.
- While both statements are true, the reason does not explain why the head of the cockroach is considered hypognathous. The orientation of the head is a separate anatomical characteristic that is not explained by the structure of the lower lip.

### Step 4: Conclusion
Based on the analysis:
- The assertion is true.
- The reason is true, but it does not provide a justification for the assertion.

### Final Answer
- Both the assertion and reason are true, but the reason does not correctly explain the assertion.

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