Which factor accounts for the variability in individual sensitivity to radiation effects?

• A. Dose rate
• B. Sensitivity of the affected individual
• C. Type of radiation
• D. Acute exposure

Answer: (B)

The main idea is that people differ in how susceptible they are to radiation because of intrinsic biological factors. Radiation causes DNA damage, and how severely someone is affected depends on their body's ability to repair that damage and on how actively their cells are dividing. Some individuals have genetic differences that reduce DNA repair efficiency or otherwise heighten sensitivity, and age or health status can also influence how strongly tissues respond. Therefore, the variability in how individuals respond is driven by their inherent radiosensitivity.

Keep in mind that dose rate, radiation type, and whether exposure is acute shape the overall risk for a given person, but they don’t explain why two people with the same exposure might experience different effects. For example, a person with higher innate radiosensitivity or with conditions affecting DNA repair is more likely to show greater effects than someone with greater repair capacity, even under identical exposure.