Cultural exchange plays an important role_____promoting relation

Cultural exchange plays an important role_____promoting relation between the two countries.
A、in
B、on
C、at
D、to
【正确答案】：A
【题目解析】：考查固定搭配。句意：文化交流在促进两国关系方面发挥着重要作用。play an important role in…为固定搭配，意为“在……中起重要作用”。