问题补充：
---Nice to meet you, Mike. ?
---Everything is OK. Thanks.
A. What did you do
B. How are you
C. How is it going
D. What happened
答案：
A. What did you do
B. How are you
(答案→)C. How is it going
D. What happened
解析：What did you do你做了什么；How are you你好吗；How is it going情况怎么样；What happened发生了什么？句意：很高兴遇到你，麦克。根据下文，一切都好。多谢。可知选C，最符合语境。
