Answer:
C. transgressed
Explanation:
He often transgressed the school code of conduct and was frequently in detention.
This would be the correct version of this word for this sentence. We can determine this due to some of the other keywords within the sentence such as "often" and "was". Both of these words indicate that the sentence takes place in past tense. Therefore, the only proper version of the word that would fit as past tense is "transgressed"