Population of an insect species increases explosively during rainy season. It disappears at the end of the season due to

Options

A. Death of food plants at the end of rainy season
B. J-shaped growth curve
C. Increase in predator population
D. S-shaped growth curve

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question states that the population of an insect species increases explosively during the rainy season and disappears at the end of the season. We need to determine the reason for this sudden disappearance.

2. **Analyzing Population Dynamics**: During the rainy season, favorable conditions such as abundant food and suitable habitat likely lead to a rapid increase in the insect population. This is characterized by a J-shaped growth curve, where the population grows exponentially.

3. **Identifying Factors for Disappearance**: At the end of the rainy season, several factors could contribute to the decline in the insect population:
- Lack of food resources as the rainy season ends.
- Environmental conditions becoming unfavorable.
- Possible increase in predator populations that could lead to higher mortality rates.

4. **Evaluating the Options**:
- **Death of food plants at the end of the rainy season**: This could lead to food scarcity, but it does not explain the explosive growth during the rainy season.
- **J-shaped growth curve**: This accurately describes the population dynamics observed, where the population grows rapidly and then declines sharply.
- **Increase in predator population**: This could also contribute to the decline, but it does not fully explain the initial explosive growth.
- **S-shaped growth curve**: This describes a scenario where population growth is limited by carrying capacity, which does not fit the context of explosive growth followed by a sharp decline.

5. **Conclusion**: The most fitting explanation for the explosive increase followed by a disappearance is the **J-shaped growth curve**. This indicates that the population can grow rapidly under favorable conditions but may decline sharply when those conditions change.

### Final Answer:
The population of the insect species disappears at the end of the rainy season due to a **J-shaped growth curve** (Option B).

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