Explain why Protozoa are categorized as heterotrophs?

Explanation

**Step-by-Step Solution:**

1. **Definition of Protozoa**: Protozoa are unicellular organisms that belong to the Kingdom Protista. They are eukaryotic, meaning they have a well-defined nucleus and various cell organelles.

2. **Understanding Heterotrophs**: Heterotrophs are organisms that cannot produce their own food. Instead, they rely on other organisms for their nutritional needs. This is in contrast to autotrophs, which can create their own food through processes like photosynthesis.

3. **Nutritional Habits of Protozoa**: Most protozoa are categorized as heterotrophs because they do not have the ability to synthesize their own food. They obtain their nutrients by consuming other organisms or organic matter.

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