______ your letter of April 16, I have to inform you that we no longer have any of the goods you want.
A、In return to
B、In reply to
C、In regard to
D、In response to
【正确答案】：B
【题目解析】：A项：作为报答；B项：回复；C项：关于；D项：回答；题意：回复你4月16号的来信，排除A、C项；B项侧重于邮件、信件的回答，D项侧重于口头的回答，B项符合题意。
