题目

Seeing Danel went into the classroom with tears in his eyes, I asked him what . A . happened B . had happened C . would happen D . was happened 答案：B我国学者普遍认为,精耕细作是我国古代农业的基本特点。以下史料能够佐证这一观点的有(　　) ①《荀子·王制》:“凡农之道,厚(候)之为宝。” ②《农书·粪田之宜》: “用粪犹用药也。” ③《商君书·垦令》:“使民无得擅徙,则诛愚。乱农之民无所于食而必农。” ④《齐民要术》:“麦黄种麻,麻黄种麦。” A.①②③      B.②③④      C.①②④      D.①③④