信函写作的7C原则 — 国际贸易选择题

某业务员起草的付款催促函中写道："You have unreasonably delayed payment for two months, which has caused us great losses. If you do not settle the account immediately, we will have no choice but to take legal action against you." 该句同时违反了7C原则中的哪两项？A. Completeness 和 Concreteness　B. Courtesy 和 Consideration　C. Clarity 和 Conciseness　D. Concreteness 和 Correctness