Final answer:
Alpha radiation causes the most biological damage when the source is inside the body, due to its high energy absorption by tissues, while gamma radiation is most dangerous from an external source due to its penetrating ability.
Step-by-step explanation:
The type of radiation that would produce the greatest amount of biological damage in human tissue when the source is inside the body is alpha radiation. Alpha particles are the least penetrating, but have a high potential for causing damage if they are emitted within the body, as tissues absorb all of their energy.
On the other hand, gamma radiation is the most penetrating and can be the most dangerous when it comes from an external source. However, when considering the relative biological effectiveness (RBE), the damage also depends on where the radiation source is located (inside or outside the body), the type of radiation, and the type of tissue it affects.