How many Chinese students are involved in the conference

A．To give students a chance to debate international affairs and to mirror the real life business of the UN.
B．To enlarge students' fields of vision.
C．To learn about other cultures.
D．To learn about how to portray their own.

A．Remaining stable all the time.
B．Appearing bright red.
C．Looking dark most of the time.
D．Changing from bright to dark or vice vers