Which of the following instruments measures respiration?

Options

A. Potometer
B. Spectrophotometer
C. Anemometer
D. None of these

Answer

To answer the question "Which of the following instruments measures respiration?", we will analyze each option provided and determine which one, if any, is correct.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- Option 1: Potometer
- Option 2: Spectrophotometer
- Option 3: Anemometer
- Option 4: None of these

2. **Evaluate Option 1 - Potometer**:
- A potometer is used to measure the rate of water uptake in plants, not respiration. Therefore, this option is incorrect.

3. **Evaluate Option 2 - Spectrophotometer**:
- A spectrophotometer measures the amount of light absorbed by a sample solution. It is not designed to measure respiration. Thus, this option is also incorrect.

4. **Evaluate Option 3 - Anemometer**:
- An anemometer is an instrument that measures wind speed and pressure. It does not measure respiration, making this option incorrect as well.

5. **Evaluate Option 4 - None of these**:
- Since none of the previous options measure respiration, this option is correct. The instrument that actually measures respiration is called a respirometer.

### Conclusion:
The correct answer to the question is **Option 4: None of these**.

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