Chemoautotrophs do not need

Options

A. `H_(2)S`
B. Nitrite
C. Ammonium compounds
D. Sunlight.

Answer

**Step-by-Step Solution:**

1. **Understanding Chemoautotrophs**: Chemoautotrophs are organisms that can synthesize their own food using chemical energy derived from inorganic compounds. Unlike photoautotrophs, which use sunlight for energy, chemoautotrophs rely on chemical reactions.

2. **Identifying Nutritional Modes**: In the context of bacteria, there are two primary modes of nutrition:
- Autotrophic: Organisms that produce their own food (e.g., chemoautotrophs and photoautotrophs).
- Heterotrophic: Organisms that obtain food by consuming other organisms.

3. **Role of Sunlight**: Photoautotrophs utilize sunlight to convert carbon dioxide and water into glucose and oxygen through photosynthesis. In contrast, chemoautotrophs do not use sunlight; instead, they derive energy from chemical reactions involving inorganic substances.

4. **Conclusion**: Since chemoautotrophs do not rely on sunlight for their energy needs, the correct answer to the question "Chemoautotrophs do not need" is **sunlight**.

**Final Answer**: Chemoautotrophs do not need sunlight.

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