Vivipary is characteristic of

Options

A. mesophytes
B. xerophytes
C. hygrophytes
D. halophytes

Explanation

### Step-by-Step Solution:

1. **Understanding Vivipary**: Vivipary refers to the germination of seeds while they are still attached to the parent plant. This means that the embryo develops into a seedling before it is shed.

2. **Identifying Plant Groups**: To determine which group of plants exhibits vivipary, we need to consider the different types of plants:
- **Mesophytes**: These plants thrive in moderate water conditions. They do not typically exhibit vivipary.
- **Xerophytes**: These are adapted to dry environments and have minimal water requirements. They also do not show vivipary.
- **Hygrophytes**: These plants grow in very moist or aquatic environments. They are not known for vivipary either.
- **Halophytes**: These plants are adapted to high salinity conditions, often found in coastal areas or salt marshes. They are known to exhibit vivipary.

3. **Conclusion**: Based on the definitions and characteristics of the different plant groups, vivipary is characteristic of halophytes, which can grow in saline conditions and allow for seed germination while still attached to the parent plant.

### Final Answer:
Vivipary is characteristic of **halophytes**.

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