Many of them turned a deaf ear to his advice， they knew it to be valuable.
A. as if
B. now that
C. even though
D. so that
网友回答
A. as if
B. now that
(答案→)C. even though
D. so that
解析：“Many of them turned a deaf ear to his advice”和“they knew it to be valuable”意思相反，四个选项中引导让步状语从句的even though最为适合。