The biological middlemen SPAC is

Options

A. Atmosphere
B. Plant
C. Soil
D. Animals

Answer

**Step-by-Step Text Solution:**

1. **Understanding SPAC**: The term SPAC refers to the Soil-Plant-Atmosphere Continuum. It describes the interconnected relationship between soil, plants, and the atmosphere, which is crucial for processes like water and nutrient transport.

2. **Identifying the Biological Middleman**: The question asks for the biological middleman in the SPAC. The options provided are soil, plant, atmosphere, and animals.

3. **Eliminating Incorrect Options**:
- Animals cannot be considered as they are not part of the SPAC. The focus is solely on soil, plants, and the atmosphere.
- Soil and atmosphere cannot connect directly; they need a mediator.

4. **Analyzing the Role of Plants**:
- Plants are the living organisms that link soil and atmosphere. They absorb water and nutrients from the soil and release water vapor into the atmosphere through processes like transpiration.
- Therefore, plants serve as the intermediary between soil and atmosphere.

5. **Conclusion**: Since plants are the only entities that connect both soil and atmosphere, they are the biological middleman in the SPAC. Thus, the answer is **Plant**.

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