The function of pollen tube is

Options

A. To support nucellus development
B. To carry tube nuclei for nutrition
C. To carry sperm
D. It is vestigial organ

Answer

### Step-by-Step Solution

1. **Understanding the Pollen Tube**: The pollen tube is a structure that forms after a pollen grain lands on the stigma of a flower. It is crucial for the process of fertilization in flowering plants.

2. **Function of the Pollen Tube**: The primary function of the pollen tube is to transport male gametes (sperm cells) from the pollen grain to the ovule, where fertilization occurs.

3. **Supporting Nucellus Development**: While the pollen tube does play a role in the overall reproductive process, its main function is not to support the development of the nucellus. The nucellus is part of the ovule and is involved in the development of the embryo sac.

4. **Role of the Tube Nucleus**: The tube nucleus, which is part of the pollen tube, helps guide the pollen tube towards the ovule. It does not carry nutrients; instead, it plays a role in the growth and direction of the pollen tube.

5. **Clarifying Misconceptions**: The pollen tube is not a vestigial organ. Vestigial organs are remnants of structures that had a function in ancestral species but no longer serve a purpose. The pollen tube is actively involved in the fertilization process.

6. **Conclusion**: Therefore, the correct function of the pollen tube is to transport male gametes to the ovule for fertilization.

### Final Answer
The function of the pollen tube is to transport male gametes (sperm cells) to the ovule for fertilization.

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