Assertion: In honeybee, males are always haploid. Reason: They are derived from unfertilised eggs.

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 Solution:**

1. **Understanding the Assertion**: The assertion states that in honeybees, males are always haploid. This means that male honeybees, known as drones, have only one set of chromosomes.

2. **Understanding the Reason**: The reason provided is that male honeybees are derived from unfertilized eggs. In honeybee reproduction, the type of egg determines the ploidy level of the offspring.

3. **Honeybee Reproduction**: In honeybee colonies, there are three types of bees: drones (males), queens (females), and worker bees (females). Drones are produced from unfertilized eggs, while queens and workers are produced from fertilized eggs.

4. **Chromosome Count**: Male honeybees (drones) have a haploid chromosome number, which is half of the diploid number. In honeybees, the haploid number is 16 chromosomes (1 set), while the diploid number for queens and workers is 32 chromosomes (2 sets).

5. **Conclusion**: Since drones are indeed derived from unfertilized eggs and have a haploid chromosome number, both the assertion and reason are true. Furthermore, the reason correctly explains the assertion.

6. **Final Statement**: Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

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