TOEFL Reading: ETS-TOEFL阅读机经 - 3SVHD7Q75T71HX3SL$

Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. A. Although experts can detect the changes that occur in different performances, the changes are too subtle to be noticed by anyone else. B. Although their performances vary only subtly from one night to another, actors in most professional productions want audiences to believe that every performance is unique. C. Everyone involved in the professional production of a play knows that very small, almost unnoticeable changes make each performance unique. D. In most professional productions, changes are included from one performance to another that are intended to make every performance a unique one.