Motile, bi-flagellated antherozoids are found in
1 Anthoceros
2 Pinus
3 Selaginella
4 Both (1) and ( 3)

Options

A. Anthoceros
B. Pinus
C. Selaginella
D. Both (1) and ( 3)

Answer

To determine where motile, bi-flagellated antherozoids are found, we can analyze each option provided in the question step by step.

### Step 1: Understanding Antherozoids
Antherozoids are the male gametes produced in certain plants. They are motile and bi-flagellated, which means they have two flagella that help them move. This characteristic is typically found in certain groups of plants, particularly bryophytes and pteridophytes.

### Step 2: Analyzing the Options
1. **Anthoceros**: This is a genus of hornworts, which are classified as bryophytes. Bryophytes are known to produce motile, bi-flagellated antherozoids. Therefore, this option is correct.

2. **Pinus**: Pinus is a genus of gymnosperms. Gymnosperms do not produce motile antherozoids; instead, they produce pollen grains, which are non-motile male gametophytes. Thus, this option is incorrect.

3. **Selaginella**: Selaginella is a genus of pteridophytes (ferns and their relatives). Pteridophytes are known to produce motile, bi-flagellated antherozoids. Therefore, this option is also correct.

4. **Both (1) and (3)**: Since both Anthoceros (bryophyte) and Selaginella (pteridophyte) produce motile, bi-flagellated antherozoids, this option is correct as well.

### Conclusion
The correct answer is **Both (1) and (3)**, as both Anthoceros and Selaginella produce motile, bi-flagellated antherozoids.

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