________ modeling business is by no means easy to get into, the good model will always be in demand．

1. A.
   While
2. B.
   Since
3. C.
   As
4. D.
   If

____________ modeling business is by no means easy to get into, the good model will always be in demand.  

____________ modeling business is by no means easy to get into, the good model will always be in demand.  

A. While                           B. Since                          C. As                            D. If

____ modeling business is by no means easy to get into, the good model will always be in demand.

A. While               B. Since                C. As                    D. If