A large _____ of chemical waste ______ been dumped in the river, causing serious water pollution.

A．number; has    B．quantity ; has        C．number ; have        D．quantity; have

A large ________ of chemical waste ________ been dumped in the river, causing serious water pollution．

1. A.
   number; has
2. B.
   quantity; has
3. C.
   number; have
4. D.
   quantity; have