The correct answer is B) Please clarify the issue, so we can understand.
Explanation:
The use of formal language implies avoiding any colloquialisms, informal words, slangs, contractions and using appropriate terms. Also, in formal language, the tone is objective or impersonal and grammar is strictly followed.
According to this, the sentence that is the most appropriate to use in a formal, written request is "Please clarify the issue, so we can understand" because this sentence avoids informal language such as contractions or colloquial words and uses appropriate terms such as "clarify the issue", also is grammatically correct and has an objective tone as it avoids using words such as "I" or "you".
