Male and female gametophytes are independent and free-living in

Options

A. Castor
B. Pinus
C. Sphagnum
D. Mustard.

Answer

To solve the question "Male and female gametophytes are independent and free-living in," we will analyze the options provided: Castor, Pinus, Sphagnum, and Mustard.

### Step-by-Step Solution:

1. **Understand the terms**:
- Gametophytes are the sexual phase in the plant life cycle that produces gametes (sperm and eggs).
- In some plants, gametophytes are independent and free-living, while in others, they are dependent on the sporophyte (the asexual phase).

2. **Analyze each option**:
- **Castor**: This is an angiosperm (flowering plant). In angiosperms, the gametophytes are usually not free-living; they develop within the flower structure.
- **Pinus**: This is a gymnosperm (non-flowering plant). In gymnosperms, the male and female gametophytes are also dependent on the sporophyte for nourishment and protection.
- **Sphagnum**: This is a type of bryophyte (moss). In bryophytes, the gametophyte is the dominant phase of the life cycle and is independent and free-living. Both male and female gametophytes can exist separately and are not dependent on the sporophyte.
- **Mustard**: Like Castor, this is also an angiosperm. The gametophytes are not free-living and are contained within the ovule and pollen.

3. **Determine the correct answer**:
- Since Sphagnum is a bryophyte where both male and female gametophytes are independent and free-living, it is the correct answer.

### Final Answer:
The correct answer is **Sphagnum**.