By nine o'clock, all the Olympic torch b
题型：选择题
问题：
By nine o'clock, all the Olympic torch bearers had reached the top of Mount Qomolangma, ____ appeared
a rare rainbow soon.
[ ]
A. of which
B. on which
C. from which
D. above which
By nine o'clock, all the Olympic torch bearers had reached the top of Mount Qomolangma, ____ appeared
a rare rainbow soon.
[ ]
A. of which
B. on which
C. from which
D. above which