Assertion: Catfishes are the best culturable fishes.
Reason: Catfishes survive even at high temperature and low oxygen.

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 and the Reason is not the Reason is not the correct explanation of the assertion
C. If assertion is true but the Reason are false
D. If assertion is False but the Reason is true

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Catfishes are the best culturable fishes." This implies that catfishes are considered the most suitable for aquaculture practices.

2. **Evaluating the Reason:**
- The reason given is that "Catfishes survive even at high temperature and low oxygen." This indicates a specific adaptability of catfishes to challenging environmental conditions.

3. **Analyzing the Truth of the Assertion:**
- Although catfishes have certain advantages, such as their ability to survive in less-than-ideal conditions, they are not universally regarded as the best culturable fishes. In fact, their introduction can threaten indigenous fish species and lead to ecological imbalances. Therefore, the assertion is **false**.

4. **Analyzing the Truth of the Reason:**
- The reason provided is accurate; catfishes do indeed have a high tolerance for both elevated temperatures and low oxygen levels. This adaptability is a factual characteristic of catfishes, making the reason **true**.

5. **Conclusion:**
- Since the assertion is false and the reason is true, the correct relationship between the two is that the reason does not adequately support the assertion. Thus, the answer is that the assertion is false and the reason is true.

**Final Answer:**
- Assertion: False
- Reason: True

**Option D is the correct choice.**

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