In          world of uncertain energy prices, light rail looks like         smart choice.

       A．the; the               B．不填；a              C．a; a                     D．a; 不填

In _____ world of uncertain energy prices, light rail looks like___ smart choice.

A．the, the                   B．/, a                  C．a, a                   D．a, the  

In ________ world of uncertain energy prices, light rail looks like ________ smart choice．

1. A.
   the, the
2. B.
   /; a
3. C.
   a; a
4. D.
   a;/