You should go to see him when he is so seriously ill. , he is your brother.
A. Because
B. After all
C. At all
D. Above all
网友回答
A. Because
(答案→)B. After all
C. At all
D. Above all
解析：考查短语辨析。A因为（引导原因状语从句）B毕竟；终究；C根本，全然；D首先，最重要的是；句意：当他生病的时候，你应该去看看他的，毕竟，他是你兄弟。After all作为：毕竟。提醒对方不要忘记…。故B正确。