After two years of working on the subject,
题型：单项选择题
问题：
After two years of working on the subject, he seriously switched his field again, ______ to comparative anatomy and physiology.
A. transferring
B. gliding
C. transforming
D. drifting
After two years of working on the subject, he seriously switched his field again, ______ to comparative anatomy and physiology.
A. transferring
B. gliding
C. transforming
D. drifting