Lately some scientists are experimenting
题型：选择题
问题：
Lately some scientists are experimenting _____ white mice to _____ this kind of medicine. [ ]
A. on, try on
B. with, test on
C. on, test out
D. with, carry out
Lately some scientists are experimenting _____ white mice to _____ this kind of medicine. [ ]
A. on, try on
B. with, test on
C. on, test out
D. with, carry out