Which of the following statement is not correct ?

Options

A. In gymnosperms the sporophyte and the gametophyte do not have an independent free-living existence.
B. The leaves of gymnosperms are well-adapted to withstand extremes of tempertature humidty and wind.
C. Pollination in gymnosperms is mainly carried by air current
D. The muticellular female gametophyte of gymnosperm is retained within megasporangium.

Answer

To determine which statement is not correct regarding gymnosperms, we will analyze each of the four statements provided.

### Step-by-Step Solution:

1. **Analyze Statement 1**: "In gymnosperms, the sporophyte and gametophyte do not have an independent free-living existence."
- **Explanation**: This statement is incorrect. In gymnosperms, both the sporophyte (the dominant phase) and the gametophyte (which is reduced) can have independent existence. The sporophyte is the tree itself, while the gametophyte is found within the cones. Therefore, this statement is false.

2. **Analyze Statement 2**: "The leaves of gymnosperms are well adapted to withstand extremes of temperature, humidity, and wind."
- **Explanation**: This statement is correct. Gymnosperms, such as conifers, have needle-shaped leaves that minimize water loss and are adapted to harsh environmental conditions. These adaptations help them survive in extreme climates.

3. **Analyze Statement 3**: "Pollination of gymnosperms is mainly carried out by air currents."
- **Explanation**: This statement is also correct. Gymnosperms do not have flowers, and their pollination is primarily facilitated by wind (abiotic factor), making this statement true.

4. **Analyze Statement 4**: "The multicellular female gametophyte of gymnosperms is retained within the mega-sporangium."
- **Explanation**: This statement is correct as well. In gymnosperms, the female gametophyte develops within the ovule, which is part of the mega-sporangium, until fertilization occurs.

### Conclusion:
After analyzing all four statements, we find that **Statement 1** is the only incorrect statement. Thus, the answer to the question is that the first statement is not correct.