The gametophyte is not an independent, free-living generation in

Options

A. Polytrichum,Cycas,Equisetum
B. Adiantum
C. Marchantia
D. Pinus

Answer

To solve the question "The gametophyte is not an independent, free-living generation in," we will analyze the options provided and understand the characteristics of gametophytes in different plant groups.

### Step-by-Step Solution:

1. **Understand the Concept of Gametophytes**:
- Gametophytes are the haploid phase in the plant life cycle that produces gametes (sperm and eggs). In some plant groups, gametophytes can exist independently, while in others, they are dependent on the sporophyte.

2. **Identify the Groups of Plants**:
- The question provides four options: Polytrichum, Cyclicosetum, Marchantia, and Pinus. We need to classify these plants into their respective groups.

3. **Classify Each Option**:
- **Polytrichum**: This is a bryophyte. In bryophytes, the gametophyte is the dominant and independent phase.
- **Cyclicosetum**: This is also a pteridophyte. In pteridophytes, the gametophyte is usually independent but the sporophyte is the dominant phase.
- **Marchantia**: This is another bryophyte. Similar to Polytrichum, the gametophyte is independent.
- **Pinus**: This is a gymnosperm. In gymnosperms, the male and female gametophytes do not have an independent existence; they are retained within the sporophyte.

4. **Determine the Correct Answer**:
- Since we are looking for the plant in which the gametophyte is not an independent, free-living generation, we find that only **Pinus** fits this description. The gametophytes in Pinus are dependent on the sporophyte and do not exist independently.

5. **Conclusion**:
- Therefore, the answer to the question is **Pinus**.

### Final Answer:
**Pinus**