—Did you find the missing couple in the mountain yesterday?
—No, but we to get in touch with them ever since.
A. have tried
B. have been trying
C. had tried
D. had been trying
网友回答
A. have tried
B. have been trying
C. had tried
D. had been trying
解析：由ever since和but 可知，自那时起到现在一直在设法与他们取得联系，所以用现在完成进行时。