The medical team ______ this area were kept busy ______ the cause of this unknown disease.

A．in charge of; in search of                             B．in search of; in charge of

C．searched for; in charge of                                   D．in charge of; in search for

The medical team ________ this area were kept busy ________ the cause of this unknown disease．

1. A.
   in charge of; in search of
2. B.
   in search of; in charge of
3. C.
   searched for; in charge of
4. D.
   in charge of; in search for