问题补充：
----Who were those young people with national flags in their hand?
-----A groupthemselves the Volunteers for the Westem Big Exploitation.
A. calling
B. to call
C. called
D. is called
答案：
(答案→)A. calling
B. to call
C. called
D. is called
解析：可联系答.案.网客服索取。
