[A]: Pollen grains from male parent are mostly transferred to the stigma in the female parent by some external ageincy. [R]: This is because the male flowers or male organs have no intemal device to reach the female organs in another flower

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

To solve the question, we need to analyze both the assertion and the reason provided, and determine their truthfulness and relationship to each other.

### Step-by-Step Solution:

1. **Understand the Assertion**:
- The assertion states that "Pollen grains from male parent are mostly transferred to the stigma in the female parent by some external agency."
- This is true because pollination, the process of transferring pollen from the male anther to the female stigma, often involves external agents such as wind, water, or animals.

2. **Understand the Reason**:
- The reason given is "This is because the male flowers or male organs have no internal device to reach the female organs in another flower."
- This statement is also true. Male reproductive structures (stamens) lack mechanisms to directly transfer pollen to female structures (pistils) in different flowers, necessitating the involvement of external agents.

3. **Evaluate the Relationship**:
- The reason explains why the assertion is true. Since male flowers do not have a way to transfer pollen directly to female flowers, they rely on external agencies for pollination.

4. **Conclusion**:
- Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer:
The correct option is: **If both assertion and reason are true and reason is the correct explanation of assertion.**

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