A:Plants which live for many years are called perennials.
R:Perennials which produce flowers and seeds only once during their life span are called monocarpic plants.

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. **Understanding the Assertion (A):**
- The assertion states that "Plants which live for many years are called perennials."
- This is true because perennials are defined as plants that have a lifespan of more than two years.

2. **Understanding the Reason (R):**
- The reason states that "Perennials which produce flowers and seeds only once during their lifespan are called monocarpic plants."
- This is also true because monocarpic plants are characterized by flowering and producing seeds only once in their lifetime.

3. **Classification of Plants:**
- Plants can be classified based on their lifespan into three categories:
- **Annuals:** Live for less than one year.
- **Biennials:** Live for one to two years.
- **Perennials:** Live for more than two years.

4. **Monocarpic vs. Polycarpic:**
- Monocarpic plants flower only once in their lifetime, while polycarpic plants can flower multiple times.
- Most monocarpic plants are annual or biennial, but some perennials can also be monocarpic.

5. **Example of Monocarpic Perennial:**
- An example of a monocarpic perennial is bamboo, which flowers only once after a long period (50 to 100 years).

6. **Conclusion:**
- Both the assertion and reason are true statements. However, the reason does not correctly explain the assertion because not all perennials are monocarpic. Therefore, the correct answer is that both statements are true, but R is not the correct explanation of A.

**Final Answer:**
- Both A and R are true, but R is not the correct explanation of A.

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