A marine angiosperm is

Options

A. Hydrilla
B. Utricularia
C. Potamogeton
D. Zostera

Answer

To determine which of the given options is a marine angiosperm, we need to analyze each option based on their habitat and characteristics.

### Step-by-Step Solution:

1. **Understand the Definition of Marine Angiosperms**:
- Marine angiosperms are flowering plants that are adapted to live in saltwater environments. They should be fully submerged or at least partially submerged in marine water.

2. **Evaluate Each Option**:
- **Option 1: Hydrilla**:
- Hydrilla is an aquatic plant but it primarily grows in freshwater environments, often in semi-solid soil. Therefore, it does not qualify as a marine angiosperm.

- **Option 2: Utricularia**:
- Utricularia, also known as bladderwort, is a carnivorous plant that typically grows in freshwater habitats. It is not fully submerged in marine environments, thus it is not a marine angiosperm.

- **Option 3: Potamogeton**:
- Potamogeton is a genus of aquatic plants that are commonly found in freshwater. They float on the surface of the water but do not thrive in marine conditions, making this option incorrect as well.

- **Option 4: Zostera**:
- Zostera, commonly known as seagrass, is a true marine angiosperm. It is fully submerged in saltwater and can grow in various marine environments. This option meets the criteria for being a marine angiosperm.

3. **Conclusion**:
- Based on the analysis, the correct answer is **Zostera**, as it is the only option that is a marine angiosperm.

### Final Answer:
**Zostera** is the marine angiosperm among the given options.

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