单选题 He also has served as chief of staff for the president of EMEA, ______ is composed of 22 subsidiaries and has its headquarters in Paris.
A. what
B. which
C. that
D. and

【正确答案】 B

【答案解析】中级问题逗号后面的句子是修饰EMEA的定语从句，空格内填入的词语是is的主语。what引导的是名词性从句；that不在逗号后面使用。如果填入and，则主语变成了he，并且句意不合适。