Cycas has the largest

Options

A. (a) ovule
B. (b) largest male gametophyte
C. (c) sperm
D. (d) all of the above.

Answer

To answer the question "Cycas has the largest," we need to analyze the options provided and understand the characteristics of Cycas, a genus of gymnosperms.

### Step-by-Step Solution:

1. **Identify Cycas**:
- Cycas is a genus of plants that belong to the group known as gymnosperms. Gymnosperms are seed-producing plants that do not form flowers or fruits.

2. **Evaluate the Options**:
- The options given are:
a. Ovule
b. Largest male gametophyte
c. Sperm

3. **Largest Ovule**:
- Cycas is known to have the largest ovules in the plant kingdom, measuring about 6 to 7 centimeters in diameter. This makes option (a) a valid choice.

4. **Largest Male Gametophyte**:
- The male gametophyte of Cycas is also considered one of the largest among plants. This is due to the size of the pollen grains, which are quite substantial. Therefore, option (b) is also a valid choice.

5. **Largest Sperm**:
- The sperm produced by Cycas is the largest in the plant kingdom, measuring about 300 microns. This size is significant enough to be visible to the naked eye, making option (c) correct as well.

6. **Conclusion**:
- Since all three options (a, b, and c) are correct, the best answer is that Cycas has the largest ovule, male gametophyte, and sperm. Thus, the correct answer is **all of the above**.

### Final Answer:
**All of the above (a, b, and c)**.