—do you speak English so well?　　 —Because I practice it with my partner every day.　　 A. Wh

问题补充：

—do you speak English so well?

—Because I practice it with my partner every day.

A. Why B. When C. Who

答案：

解析：回答语中有个because表示原因，对原因提问的用why，故选A。When对时间提问，who对身份提问。