Sex first originated in

Options

A. protistans
B. simple algae
C. angiosperms
D. both 1 and 2

Answer

To determine where sex first originated, we need to analyze the options given: Protista, simple algae, angiosperms, or both Protista and simple algae.

### Step-by-Step Solution:

1. **Understanding Protista**:
- Protista are simple eukaryotic organisms.
- They can be unicellular or multicellular but are primarily unicellular.
- They are not classified as plants, animals, or fungi.

2. **Understanding Simple Algae**:
- Algae are photosynthetic organisms that can also be unicellular or multicellular.
- They produce their own food due to the presence of chlorophyll.
- Algae evolved after protists.

3. **Understanding Angiosperms**:
- Angiosperms are vascular plants that produce flowers.
- They have true roots, stems, and leaves.
- They are considered more complex and evolved later than both protists and algae.

4. **Comparing the Origins**:
- Since protists are the simplest eukaryotic organisms and are believed to have originated first, they are likely the first organisms to exhibit sexual reproduction.
- Algae, while also early organisms, evolved after protists.

5. **Conclusion**:
- Since both Protista and simple algae are among the earliest forms of life, and since protists are considered to have originated first, the answer to the question "Sex first originated in" is **both Protista and simple algae**.

### Final Answer:
Sex first originated in **both Protista and simple algae**.

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