Relative Biological Effectiveness (RBE) usually refers to damage caused by

Options

A. low temperature
B. high temperature
C. radiation
D. pollution

Explanation

### Step-by-Step Solution:

1. **Understanding Relative Biological Effectiveness (RBE)**:
- RBE is a measure used to compare the biological effectiveness of different types of ionizing radiation. It helps in understanding how different radiation types can cause damage to biological tissues.

2. **Application of RBE**:
- RBE is primarily used in radiology labs to assess the effects of radiation on biological tissues. This is crucial in medical settings where radiation is used for diagnostic and therapeutic purposes.

3. **Mechanism of RBE Calculation**:
- RBE is calculated as a ratio of the biological effect of one type of radiation to another, given that the energy absorbed is constant. The formula can be expressed as:
\[ RBE = \frac{IR_1}{IR_2} \]
- Here, \( IR_1 \) represents the biological effect of the first type of radiation, and \( IR_2 \) represents the biological effect of the second type of radiation.

4. **Conclusion**:
- Based on the understanding of RBE, we conclude that it specifically refers to the damage caused by radiation. Therefore, the correct answer to the question is "radiation".

### Final Answer:
- The correct answer is **radiation**.

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