Assertion : Water hyacinth is an invasive aquatic plant which speads all over the water in a short period of time.
Reason : Water hyacinth can reproduce vegetatively.

Options

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

Explanation

### Step-by-Step Text Solution:

1. **Understanding the Assertion**: The assertion states that "Water hyacinth is an invasive aquatic plant which spreads all over the water in a short period of time." This is true as water hyacinth is known for its rapid growth and ability to cover large areas of water bodies quickly.

2. **Understanding the Reason**: The reason provided is that "Water hyacinth can reproduce vegetatively." This is also true. Water hyacinth primarily reproduces through vegetative propagation, which allows it to spread rapidly.

3. **Explaining Vegetative Reproduction**: Water hyacinth reproduces vegetatively by forming daughter plants at the base of the parent plant. These daughter plants remain attached to the parent until they are detached by external forces, such as water currents or physical removal.

4. **Linking Assertion and Reason**: Since the reason (vegetative reproduction) explains how the assertion (rapid spread of water hyacinth) occurs, both the assertion and reason are correct, and the reason provides a correct explanation for the assertion.

5. **Conclusion**: Therefore, both the assertion and reason are true, and the reason is the correct explanation for the assertion.

### Final Answer:
Both the assertion and reason are correct, and the reason is the correct explanation for the assertion.

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