Which sentence demonstrates correct punctuation?
A. The crowd gasped as the circus trapeze artists' acrobatically leapt from one rope to another.
B. The drivers frequently disregarded the school zone: therefore, a police officer began giving tickets.
C. The college's admissions board evaluates three things: attendance, community service, and grades.
D. The teacher told her students; "You must come to class prepared if you want to master this subject."
