46. The board of the company has decided to ______ its operations to include all aspects of the clothing business.

A) multiply          B) lengthen        C) expand                  D) stretch

 47. His business was very successful, but it was at the ______ of his family life.

A) consumption       B) credit          C) exhaustion               D) expense

 48. First published in 1927, the charts remain an ______ source for researchers.

A) identical          B) indispensable    C) intelligent                D) inevitable

 49. Joe is not good at sports, but when it ______mathematics, he is the best in the class.

A) comes to          B) comes up to     C) comes on to          D) comes around to

 50. Doctors warned against chewing tobacco as a ______ for smoking.

A) relief            B) revival          C) substitute                D) succession

46.C) expand   47. D) expense    48.B) indispensable   49.A) comes to   50.C) substitute