Assertion. Castor seed is dicot endospermic seed.
Reason. Seed is with two cotyledons and unconsumed endosperm.

Options

A. If both Assertion and Reason are true and the Reason is a correct explanation of the Assertion.
B. If both Assertion and 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 and Reason are false.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Castor seed is a dicot endospermic seed." To evaluate this, we need to recognize that dicot seeds are characterized by having two cotyledons.

2. **Identifying the Characteristics of Castor Seed**: Castor seeds belong to the family Euphorbiaceae and are known to have two cotyledons. This aligns with the definition of dicot seeds.

3. **Understanding the Reason**: The reason provided states that "the seed is with two cotyledons and unconsumed endosperm." This means that in castor seeds, the endosperm, which serves as the food reserve for the developing plant, is present and has not been fully utilized during seed development.

4. **Connecting the Assertion and Reason**: Since castor seeds have two cotyledons (indicating they are dicots) and they also retain unconsumed endosperm, both the assertion and reason are true.

5. **Conclusion**: Therefore, the assertion that "Castor seed is a dicot endospermic seed" is correct, and the reason provided supports this assertion.

### Final Answer:
Both the assertion and the reason are true, and the reason correctly explains the assertion.

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