Stephen Hawking believes that the earth is unlikely to be the only planet     _life has developed gradually.

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

Stephen Hawking believes that the earth is unlikely to be the only planet _______ life has developed gradually.

Stephen Hawking believes that the earth is unlikely to be the only planet _______ life has developed gradually.

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

Stephen Hawking believes that the earth is unlikely to be the only planet     _life has developed gradually.        

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

Stephen Hawking believes that the earth is unlikely to be the only planet          life has developed gradually.  

A. whose           B. where           C. which           D. what