One of the following is an autotroph. This one is :

Options

A. alligator
B. algae
C. antelope
D. ant

Answer

### Step-by-Step Solution:

1. **Understanding the Term "Autotroph":**
- An autotroph is an organism that can produce its own food. This is typically done through a process called photosynthesis, where organisms convert light energy into chemical energy.

2. **Identifying the Options:**
- The options given are:
- Alligator
- Algae
- Antelope
- Ant

3. **Analyzing Each Option:**
- **Alligator:** This is a carnivorous reptile that cannot produce its own food. It is a heterotroph.
- **Algae:** Algae are simple, aquatic organisms that can perform photosynthesis. They contain chlorophyll and can produce their own food, making them autotrophs.
- **Antelope:** This is a herbivorous mammal that relies on plants for food, hence it is a heterotroph.
- **Ant:** Ants are insects that depend on other organisms for food, making them heterotrophs.

4. **Conclusion:**
- Among the options, **Algae** is the only organism that can produce its own food through photosynthesis, categorizing it as an autotroph.

### Final Answer:
The correct answer is **Algae**.

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