The company has a free long-distance telephone number_____ customers may call with any questions they have about the products .

1. A.
   when
2. B.
   so that
3. C.
   while
4. D.
   as

 The company has a free long-distance telephone number_____ customers may call with any questions they have about the products .

 A. when　　B. so that 　　C. while　　D. as

 The company has a free long-distance telephone number _____ customers may call with any questions they have about its products.
   A. although           B. as              C. even if             D. so that

The company has a free long-distance telephone number_____ customers may call with any questions they have about its products.

　　 A. so that　 B. although　 C. as　　 D. even if

The company has a free long-distance telephone number ________ customers may call with any questions they have about its product .

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