Final answer:
The pair that is mismatched is ionizing radiation - hydroxyl radicals. Ionizing radiation refers to radiation with enough energy to remove tightly bound electrons from atoms, resulting in the formation of free radicals like hydroxyl radicals. Hydroxyl radicals are formed by the knockoff of an electron from water molecules by ionizing radiation, not the other way around.
Step-by-step explanation:
The pair that is mismatched is ionizing radiation - hydroxyl radicals. Ionizing radiation refers to radiation with enough energy to remove tightly bound electrons from atoms, resulting in the formation of free radicals like hydroxyl radicals. Hydroxyl radicals are formed by the knockoff of an electron from water molecules by ionizing radiation, not the other way around. Therefore, this pair is mismatched.