Which type of radiation can penetrate the skin but not deep tissue?

Beta radiation is indeed the correct choice. It consists of high-energy, high-speed electrons or positrons that are emitted by certain types of radioactive nuclei. Due to their relatively small mass and charge, beta particles can penetrate the skin and are capable of reaching the outer layers, such as the epidermis. However, they tend to lose energy more rapidly than other types of radiation as they interact with matter, making their ability to penetrate deeper tissue significantly limited.

In contrast, alpha radiation consists of heavier helium nuclei that can be stopped by a sheet of paper or the outer layer of skin, hence they do not penetrate skin at all. Gamma radiation has much higher energy and is capable of penetrating deep into tissues, sometimes requiring heavy shielding for complete blockage. Neutron radiation, although penetrating, can interact with matter in a different way that might lead to deeper tissue penetration.

Thus, the properties of beta radiation make it unique in its ability to penetrate the skin without being able to reach into deeper tissues, which is why it is the correct answer for the question asked.