Motile, bi-flagellated antherozoids are found in `:`

Options

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

Answer

To solve the question regarding where motile, bi-flagellated antherozoids are found, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Term "Antherozoids":**
- Antherozoids are the male gametes produced in the male reproductive organs of plants, specifically in antheridia.

2. **Identify the Characteristics of Antherozoids:**
- The question specifies that the antherozoids are motile and bi-flagellated.
- "Motile" means that they can move, and "bi-flagellated" means that they have two flagella which aid in their movement.

3. **Determine the Plant Groups:**
- Antherozoids are primarily associated with certain groups of plants, particularly bryophytes (like mosses and liverworts) and some pteridophytes (like ferns).

4. **Identify Specific Examples:**
- Among bryophytes, the genus **Anthoceros** is known to produce motile, bi-flagellated antherozoids.
- In addition, the genus **Selaginella**, which is a type of pteridophyte, also produces motile, bi-flagellated antherozoids.

5. **Select the Correct Answer:**
- Given the options, both **Anthoceros** and **Selaginella** have motile, bi-flagellated antherozoids. Therefore, the correct answer is that motile, bi-flagellated antherozoids are found in **both Anthoceros and Selaginella**.

### Final Answer:
Motile, bi-flagellated antherozoids are found in **Anthoceros and Selaginella**.

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