When _______ different cultures, we often pay attention only to the differences without noticing the many similarities.
A. compared          B. being compared   
C. comparing         D. having compared

【答案】：C
【解析】：因为句子的主语是we, compare的逻辑主语也是we，且we与compare之间是主动关系，因此应用现在分词作状语，所以C正确。