A land plant produces flagellated sperm and the dominant generation is diploid. The plant is most likely :

Options

A. fern
B. moss
C. dicot
D. conifer

Explanation

To solve the question "A land plant produces flagellated sperm and the dominant generation is diploid. The plant is most likely:", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Key Features**: The question states that the plant produces flagellated sperm and has a diploid dominant generation. This indicates that we are looking for a plant group where the sporophyte (diploid phase) is the dominant form and produces flagellated sperm.

2. **Understand Plant Generations**: In the plant kingdom, there are two main generations: the sporophyte (diploid) and the gametophyte (haploid). In most land plants, the sporophyte generation is dominant in certain groups.

3. **Classify the Plant Groups**:
- **Bryophytes** (e.g., mosses) have a dominant gametophyte generation and produce non-motile sperm.
- **Pteridophytes** (e.g., ferns) have a dominant sporophyte generation and produce flagellated sperm (also known as antherozoids).
- **Gymnosperms** (e.g., conifers) and **Angiosperms** (e.g., dicots) also have a dominant sporophyte generation, but they do not produce flagellated sperm.

4. **Select the Correct Group**: Since the question specifies that the plant produces flagellated sperm and has a diploid dominant generation, the only suitable group is the Pteridophytes.

5. **Identify the Example**: Among the options provided, ferns are a well-known example of Pteridophytes, which produce flagellated sperm and have a dominant diploid sporophyte generation.

### Conclusion:
The plant is most likely a **fern**, which is a type of Pteridophyte.

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