The couple felt most angry about the way ________ the waiter of the hotel treated them．

1. A.
   by which
2. B.
   in which
3. C.
   for which
4. D.
   with which

The couple felt most angry about the way ________ the waiter of the hotel treated them.

A．by which                   B．in which                 C．for which             D．with which