Answer;
D. Moles or marks on the body
Moles or marks on the body could be used as evidence in proving someone was a witch
Explanation;
Moles, birthmarks, scars, extra nipples and any other blemish were considered the "Devils Mark". The Devils mark could supposedly change shape and color, and was believed to be numb and insensitive to pain.
Witch-hunters often had their suspects stripped and publicly examined for signs of an unsightly blemish that witches were said to receive upon making their pact with Satan.