还盘信函的写作技巧 — 国际贸易选择题

外贸函电中，买方收到卖方报盘后，希望卖方降低价格并延长交货期。写还盘信函时，下列哪种开头表达最符合还盘信函的写作技巧？A. Thank you for your offer of May 5. While the quality is satisfactory, we find your price too high to accept. B. Your offer is totally unacceptable and we refuse it. C. We have no interest in your products at all. D. Please send us your catalogue immediately.