No one knows how the huge rocks   and ___ without our modern machines eight hundred years ago.

A．are cut; moved

B．were cut; move

C．are cut; moving

D．were cut; moved

服用以下哪种药物可出现舌苔及大便呈灰黑色，停药后可自行消失（）

A.多潘立酮

B.枸橼酸铋钾

C.甲氧氯普胺

D.复方氢氧化铝