The majority of bacteria are-

Options

A. Photoautotrophs
B. Chemoautotrophs
C. Chemoheterotrophs/decomposers
D. Disease causing

Answer

**Step-by-Step Solution:**

1. **Understanding Bacteria's Nutrition**: Bacteria can be classified based on their nutritional modes. The main categories include photoautotrophs, chemoautotrophs, chemohydrotrophs (decomposers), and heterotrophs.

2. **Defining Chemoheterotrophs**: Chemoheterotrophs are organisms that cannot synthesize their own food. They depend on other organic or inorganic compounds for energy and carbon. This means they obtain energy by oxidizing these compounds.

3. **Identifying the Majority**: Among the various types of bacteria, the majority are classified as chemoheterotrophs. This classification indicates that they play a significant role in ecosystems by decomposing organic matter.

4. **Environmental Adaptations**: Many chemoheterotrophic bacteria thrive in extreme environments, such as deep-sea habitats or other harsh conditions. These bacteria are often referred to as extremophiles.

5. **Conclusion**: Based on the understanding of bacterial nutrition and their ecological roles, we conclude that the majority of bacteria are chemoheterotrophs or decomposers.

**Final Answer**: The majority of bacteria are chemoheterotrophs (decomposers).

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