Which one of the following organisms reproduces sexually only once in its life time ?

Options

A. Banana plant
B. mango
C. Tomato
D. Eucalyptus

Explanation

To determine which organism reproduces sexually only once in its lifetime, we need to analyze the given options: banana plant, mango, tomato, and eucalyptus.

### Step-by-Step Solution:

1. **Understanding the Concept of Monocarpic Plants**:
- Monocarpic plants are those that flower and reproduce only once in their lifetime. After they reproduce, they typically die.

2. **Analyzing the Options**:
- **Banana Plant**: This is a monocarpic plant. It flowers and produces fruit once, after which the plant dies.
- **Mango**: This is a perennial plant that can flower and produce fruit multiple times throughout its life.
- **Tomato**: This is an annual plant that can also produce fruit multiple times in a growing season.
- **Eucalyptus**: This is a perennial tree that can flower and produce seeds multiple times in its lifetime.

3. **Identifying the Correct Answer**:
- Among the options, the banana plant is the only one that reproduces sexually only once in its lifetime, making it the correct answer.

### Final Answer:
The organism that reproduces sexually only once in its lifetime is the **banana plant**.

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