1.Though they disliked the tone of his speech,they finally d

1.Though they disliked the tone of his speech,they finally decided to _______ his suggestion for it sounded practical
A.adapt B.adopt C.use D.receive
这一题为什么选D不选B,
2.________,it is quite easy to drill a hole on it with laser.
A.Hard although the diamond is B.How hard is the diamond
C.As the diamond is hard D.Hard as the diamond is
这一题为什么不能选A呢?