Two groups of the same type of cell receive different doses of the same ionising radiation. The higher-dose group has more dead cells. Some surviving cells in both groups have altered DNA. Which conclusion follows from these results?
Radiation only kills cells, and any change in DNA must have another cause.
Radiation can cause tissue damage, and surviving cells may carry mutations.
Radiation causes mutations only in cells that die, so survivors remain unchanged.
Radiation guarantees cancer in survivors, and increasing dose prevents cell death.