Final answer:
The causes of induced DNA damage include spontaneous errors by DNA polymerase, exposure to gamma radiation, exposure to ultraviolet radiation, and exposure to intercalating agents.
Step-by-step explanation:
The causes of induced DNA damage include spontaneous errors by DNA polymerase, exposure to gamma radiation, exposure to ultraviolet radiation, and exposure to intercalating agents. Therefore, the correct answer is D. exposure to intercalating agents.