Assertion `:-` Red muscles are also called aerobic muscles.
Reason `:-` These muscles contian plenty of mitochondria which can utilise the large amount of oxygen stored in them for ATP production.

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

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Red muscles are also called aerobic muscles."
- Red muscles, also known as slow-twitch muscles, are primarily involved in endurance activities and are capable of sustained contractions.

2. **Understanding the Reason:**
- The reason given is that "These muscles contain plenty of mitochondria which can utilize the large amount of oxygen stored in them for ATP production."
- This is true because red muscles have a high density of mitochondria, which are the powerhouses of the cell. They utilize oxygen to produce ATP through aerobic respiration.

3. **Connecting Assertion and Reason:**
- Both the assertion and the reason are true. Red muscles are indeed called aerobic muscles due to their reliance on aerobic metabolism for energy production.
- The reason correctly explains why red muscles are classified as aerobic muscles, as the presence of mitochondria and oxygen storage is essential for their function.

4. **Conclusion:**
- Since both the assertion and reason are true, and the reason provides a correct explanation for the assertion, the answer to the question is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

**Final Answer:**
- Both Assertion and Reason are true, and the Reason is the correct explanation of the Assertion.

---