【单选题】

According to the passage, Michelangelo was unable to finish three-fifths of his artworks for which of the following reasons

A、He possessed a deep sense of ambiguity toward his own ideas that caused him to lose confidence in them.
B、He displayed a tendency to work quickly on one project and then abandon it in haste for another.
C、He generally felt a dissatisfaction with the ideals that served as the model for his art works.
D、He frequently felt unable to express his general ideals through a particular art work.
E、
A、heavy price was exacted upon him as an artist by the process of continual abstraction.