题目

The murder was brought in, with his hands ___ behind his back。 A. being tied    B. having tied C. to be tied    D. tied 答案：D下列关于植物生命活动调节的叙述，正确的是 A.脱落酸可抑制老叶凋落    B.常选用一定浓度的2,4­D除去田间的杂草 C.恶苗病是生长素作用的结果 D.在果树挂果时，利用乙烯利促进果实细胞体积增大