Have you ever listened to ... Backstreet Boy, ... pop band?

1. Have you ever listened to.............Backstreet Boy,................pop band?
A. the/a              B. a /X             C.X/the             D. a/a
2.I'm trying to learn...................Japanese, I'm having..................lesson tomorrow.
A.the/a               B.X/the            C.X/a                D.the/X