To solve the question of identifying the set that represents only the biotic components of a habitat, we can follow these steps:
### Step-by-Step Solution:
1. **Understand the Definitions**:
- **Biotic Components**: These are the living organisms in an ecosystem, which include plants, animals, and microorganisms.
- **Abiotic Components**: These are the non-living elements in an ecosystem, such as soil, water, air, rocks, and light.
2. **Analyze the Given Sets**:
- We need to examine each set provided in the question to identify which one contains only living organisms (biotic components).
3. **Evaluate Each Set**:
- **Set 1**: Tiger, Deer, Grass, Soil, Rocks
- Contains: Tiger (biotic), Deer (biotic), Grass (biotic), Soil (abiotic), Rocks (abiotic)
- **Conclusion**: Not all components are biotic (contains soil and rocks).
- **Set 2**: Soil, Plants, Air, Sand
- Contains: Soil (abiotic), Plants (biotic), Air (abiotic), Sand (abiotic)
- **Conclusion**: Not all components are biotic (contains soil, air, and sand).
- **Set 3**: Turtle, Crab, Rocks, Aquatic Plant
- Contains: Turtle (biotic), Crab (biotic), Rocks (abiotic), Aquatic Plant (biotic)
- **Conclusion**: Not all components are biotic (contains rocks).
- **Set 4**: Fish, Frog, Insects, Plants
- Contains: Fish (biotic), Frog (biotic), Insects (biotic), Plants (biotic)
- **Conclusion**: All components are biotic.
4. **Select the Correct Set**:
- After evaluating all the sets, we find that **Set 4** contains only biotic components.
### Final Answer:
The set that represents only the biotic components of a habitat is **Set 4: Fish, Frog, Insects, Plants**.
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