Which of the following can cause both internal and external exposure to radiation?

Radiation exposure can occur in various forms, and different types of radiation have distinct characteristics that determine how they interact with matter. The correct choice indicates that all radiation types can potentially cause both internal and external exposure under certain conditions.

For internal exposure, radiation can enter the body through inhalation, ingestion, or wounds. For example, certain radioactive isotopes can be taken up by biological systems, leading to internal exposure that can cause damage to tissues and organs. External exposure, on the other hand, occurs when radiation is present outside the body and can penetrate biological tissues.

Noble gases, such as radon, can lead to internal exposure when inhaled. Neutrons, as a type of radiation, can also induce both internal and external exposure, especially in nuclear environments. Alpha particles, while they primarily cause local damage when ingested or inhaled due to their high mass and charge, do not effectively penetrate the skin or cause external exposure in the same way that other radiation types can.

Therefore, the assertion that all types of radiation can potentially lead to both internal and external exposure accurately captures the broad spectrum of interactions that can occur between radiation and matter, which supports the choice of "all radiation types under certain conditions" as the correct answer.