For what purpose does the writer want us to know about the U.S. higher education by illustrating St. John’s College as an example?

A、tofurtherexplaindiversityasoneofthegreatstrengthsofU.S.highereducation;
B、totellusthatSt.John’sCollegeteachesthemostsubjectsintheU.S.;
C、toclarifythatSt.John’sCollegeofferstraditionalmathandsciencecourses;
D、toexplainthatU.S.highereducationisratherflexible