$ Arthropoda is the largest group in the animal kingdom.
! Honey bee shows polymorphism.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

### Step-by-Step Solution:

1. **Identify the Assertion and Reason**:
- Assertion: "Arthropoda is the largest group in the animal kingdom."
- Reason: "Honey bee shows polymorphism."

2. **Evaluate the Assertion**:
- Arthropoda is indeed the largest phylum in the animal kingdom, comprising a vast number of species including insects, arachnids, myriapods, and crustaceans. This makes the assertion true.

3. **Evaluate the Reason**:
- Polymorphism refers to the occurrence of different forms or morphs within the same species. Honey bees exhibit polymorphism as they have different castes: drones (males), queens (fertile females), and workers (infertile females). Therefore, the reason is also true.

4. **Determine the Relationship Between Assertion and Reason**:
- While both the assertion and reason are true, the reason does not explain why Arthropoda is the largest group. The assertion is about the classification of animals, while the reason pertains specifically to honey bees and their forms. Thus, the reason is not a correct explanation of the assertion.

5. **Select the Correct Option**:
- Based on the evaluations, the correct option is: "Both assertion and reason are correct, but the reason is not the correct explanation of the assertion."

### Final Answer:
- The correct answer is: **Option B** - Both assertion and reason are correct, but the reason is not the correct explanation of the assertion.

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