Many of them turned a deaf ear to his advice ______ they knew it to be valuable.
A.as ifB.now thatC.even ifD.so that在线课程C
考查连词。A似乎；B既然；C即使；D以至于；句意：他们中的很多人对他的建议充耳不闻，即使他们知道建议很有价值。