________ the necessary equipment, the seriously wounded man had to be sent to another hospital for the operation. 

A. lacking   B. Lacking of   C. For lack of   D. Lacking in

________ the necessary equipment, the seriously wounded man had to be sent to another hospital for the operation.

1. A.
   lacking
2. B.
   Lacking of
3. C.
   For lack of
4. D.
   Lacking in

________ the necessary equipment, the seriously wounded man had to be sent to another hospital for the operation.