You are supposed the work yesterday but you forgot.
A. to finish
B. to be finishing
C. to have finished
D. had finished
网友回答
A. to finish
B. to be finishing
(答案→)C. to have finished
D. had finished
解析：考查非谓语动词。be supposed to do应当做，根据语境昨天已经完成工作，故用不定式的完成时态，选C。