Assertion: Gametes are always haploid.
Reason: A haploid parent body gives rise to gametes by mitosis.

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 correct explanation of the Assertion.
C. If Assertion is true but the Reason is false.
D. If both Assertion and Reason are false.

Answer

### Step-by-Step Text Solution:

1. **Understanding the Assertion**: The assertion states that "Gametes are always haploid." This means that gametes, which are the reproductive cells (sperm and eggs), contain half the number of chromosomes compared to the somatic (body) cells of an organism.

2. **Understanding the Reason**: The reason provided is "A haploid parent body gives rise to gametes by mitosis." This indicates that if the parent organism is haploid (having one set of chromosomes), it can produce gametes through the process of mitosis, which is a type of cell division that maintains the same chromosome number.

3. **Analyzing the Assertion**: The assertion is true because gametes are indeed haploid. In sexually reproducing organisms, gametes are produced from diploid parent cells through meiosis, which reduces the chromosome number by half, resulting in haploid gametes.

4. **Analyzing the Reason**: The reason is also true. When a haploid organism (like some fungi or algae) produces gametes, it does so via mitosis. Since the parent is already haploid, the gametes produced will also be haploid.

5. **Conclusion**: Both the assertion and the reason are true. Furthermore, the reason correctly explains the assertion. Therefore, the relationship between the assertion and reason is valid.

### Final Answer:
Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

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