—I hear that Lily’s brother is a worker here.
—Look, the man is working over there is her brother.
A. who
B. whom
C. what
D. which
网友回答
(答案→)A. who
B. whom
C. what
D. which
解析：考查定语从句的关系代词。who “代替人”作主语或者宾语；whom “代替人”作宾语；what不用于宾语从句；which“代替物”作主语或者宾语；先行词为人， 在从句中作主语。 故选A。