—Come in, please. Make yourself at home. —I'm glad you like it. A. Thanks. You have a nice place here. B. Oh, this picture is so beautiful! C. Thanks. What nice food you've prepared! D OK. Let me look around your new house.
Mark was a student at this university from 1999 to 2003, _____ he studied very hard and was made Chairman of the Students’ Union.
A during which time B for which time C during whose timeD by that time