Icy temperatures have damaged thousands of trucks and trains ________ with coal, food and passengers in the most severe winter ________ in 50 years in Southern China．

1. A.
   loading; seen
2. B.
   loading; seeing
3. C.
   loaded; saw
4. D.
   loaded; seen

Icy temperatures have damaged thousands of trucks and trains        with coal, food and passengers in the most severe winter        in 50 years in Southern China.

A．loading ; seen        B．loading ; seeing         C．loaded ; saw          D．loaded ; seen