The question asks to identify the incorrect tenses used in the statement:
Because Cole wears a helmet when he struck on the head by a falling coconut ten years
ago, he has escaped serious injury in that episode.
My answer: Because Cole wore a helmet when he was struck on head by a falling coconut ten years ago, he escaped serious injury in that episode.
Doubt: It's clear from the question itself that we are talking about the precise moment when the coconut fell on Cole's head. So in this case instead of using "Because Cole was wearing a helmet, cant we simply use "Because Cole wore a helmet".
Probable reason: Cole was wearing the helmet even before the coconut fell and that's why we use "Cole was wearing..". But isn't this an assumption that we are making.