I would appreciate it       you call back this afternoon for the doctor’s appointment.

I would appreciate it       you call back this afternoon for the doctor’s appointment.

A．until             B．if                C．when             D．that

I would appreciate it ______ you call back this afternoon for the doctor’s appointment.

A.until　　　　　　 B.if　　　　　　　　 C.when　　　　　 D.that

I would appreciate it       you call back this afternoon for the doctor’s appointment.

1. A.
   until
2. B.
   if
3. C.
   when
4. D.
   that