Which of the following is an example of a Stochastic effect?

A stochastic effect refers to the probability of an effect occurring rather than the severity of the effect when it does occur. These effects are characterized by their random nature, meaning that they are not directly dose-dependent and can happen after long periods following exposure to radiation.

Cancer is considered a stochastic effect because the risk of developing cancer increases with radiation exposure, but not everyone exposed will develop cancer, and there is no threshold of exposure below which the risk is zero. This can manifest many years after the initial exposure, highlighting its unpredictable nature.

In contrast, the other effects listed, like temporary sterility, erythema, and epilation, are classified as deterministic effects. Deterministic effects have a threshold level of exposure and lead to a specific severity of harm that is directly correlated with the dose received. In these cases, the more radiation exposure a person receives, the more severe the effect will be experienced, often occurring soon after exposure. Therefore, the correct answer signifies the inherent unpredictability associated with stochastic effects.