_____ Teachers’ Day is just around the corner. I want to buy a present for my teacher, _____ that is useful but not expensive.

A. The; the one           B. /; one              C. A; one             D. /; the one

_____ Teachers’ Day is just around the corner. I want to buy a present for my teacher, _____ that is useful but not expensive.

A. The; the one　 　　　 B. /; one 　　　 C. A; one　 　　 D. /; the one