Members of group chrysophytes :-

Options

A. are found only in fresh water
B. are the chief producers in the oceans
C. are microscopic and float actively in water current
D. are only parasitic

Answer

### Step-by-Step Solution:

1. **Understanding Chrysophytes**:
- Chrysophytes are a group of algae that are primarily found in aquatic environments. They are known for their golden-brown pigments and include organisms such as diatoms and golden algae.

2. **Analyzing the Statements**:
- **Statement A**: "Members of group Chrysophytes are found in fresh water."
- This statement is partially true, as chrysophytes can be found in both freshwater and marine environments. Therefore, this statement is incorrect as it does not encompass the full range of habitats.

- **Statement B**: "Are the chief producers in the oceans?"
- This statement is correct. Diatoms, which are part of the chrysophytes, are indeed the primary producers in oceanic ecosystems, playing a crucial role in the food web.

- **Statement C**: "Are microscopic and float actively in water current?"
- While chrysophytes are microscopic, the part about them floating actively is misleading. They do not actively swim but are carried by water currents. Thus, this statement is incorrect.

- **Statement D**: "Are only parasitic."
- This statement is incorrect. While some chrysophytes can be parasitic, most are autotrophic, meaning they produce their own food through photosynthesis.

3. **Conclusion**:
- After analyzing all the statements, the only correct statement is **B**: "Are the chief producers in the oceans."

### Final Answer:
The correct answer is **B**: "Are the chief producers in the oceans."

---