Which of the following is mismatched ?

Options

A. Pollen grain—microgametophyte
B. Ovule-megagametophyte
C. Seed—immature sporophyte
D. Pollen tube- spores

Explanation

To determine which option is mismatched, we need to analyze each option provided in the question. Let's go through them one by one.

### Step-by-Step Solution:

1. **Option 1: Pollen grain - Micro gametophyte**
- Pollen grains are indeed the male gametophytes in seed plants. They are responsible for producing male gametes (sperm cells). Therefore, this option is **correct**.

2. **Option 2: Ovule - Mega gametophyte**
- The ovule is the structure that develops into a seed after fertilization and contains the female gametophyte (megagametophyte). It produces the female gametes (egg cells). Thus, this option is also **correct**.

3. **Option 3: Seed - Immature sporophyte**
- A seed is an embryonic plant that is in a dormant state and is protected by a seed coat. It develops from the fertilized ovule and contains the sporophyte stage of the plant. Therefore, this option is **correct**.

4. **Option 4: Pollen tube - Spores**
- The pollen tube is a structure that forms from the pollen grain and serves to transport sperm cells to the ovule. It is not a spore; spores are reproductive units that can develop into a new organism. Hence, this option is **incorrect** or mismatched.

### Conclusion:
The mismatched option is **Option 4: Pollen tube - Spores**.

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