Antarctic __________ we know very little is covered with thick ice all the year round.

A. which 　　　B. where 　　　　　C. that 　　　　　 D. about which

Antarctic _____ we know very little is covered with thick ice all the year round.

1. A.
   which
2. B.
   that
3. C.
   where
4. D.
   about which

Antarctic _____ we know very little is covered with thick ice all the year round.

A. which       B. that    C. where        D. about which