信函写作的7C原则 — 国际贸易选择题

某公司业务员在给新客户的回信中写道："We are in receipt of your letter and wish to inform you that the matter referred to in your letter will receive our prompt attention as soon as possible."该句的主要毛病是违反了7C原则中的哪一项？ A. Completeness（完整）　B. Conciseness（简洁）　C. Concreteness（具体）　D. Consideration（体谅）