$ Annual plants live for only one favourable season.
! Polycarpic plants are those which produces flowers and fruits many times during their life span.

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

To solve the question regarding the assertion and reason provided, we will follow these steps:

### Step 1: Understand the Assertion
The assertion states that "annual plants live for only one favorable season."
- **Analysis**: This statement is true. Annual plants complete their life cycle within one growing season, germinating, growing, flowering, and dying within that period.

### Step 2: Understand the Reason
The reason states that "polycarpic plants are those which produce flowers and fruits many times during their lifespan."
- **Analysis**: This statement is also true. Polycarpic plants can flower and produce fruits multiple times throughout their life, in contrast to monocarpic plants, which flower and fruit only once.

### Step 3: Determine the Relationship Between Assertion and Reason
Now we need to check if the reason provided is the correct explanation for the assertion.
- **Analysis**: While both statements are true, the reason does not explain why annual plants live for only one favorable season. The assertion is about the lifespan of annual plants, while the reason discusses polycarpic plants, which is unrelated to the lifespan of annual plants.

### Step 4: Choose the Correct Option
Based on the analysis:
- Assertion is correct.
- Reason is correct.
- Reason is not the correct explanation of the assertion.

Thus, the correct option is: **Option B** - "If both assertion and reason are correct, but reason is not the correct explanation of assertion."

### Final Answer
The correct answer is **Option B**.

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