慢性骨髓炎（）.
A.骨质疏松
B.关节内游离体
C.骨性强直
D.死骨形成
E.骨质增生
参考答案：D
.
“Meals on wheels” is a free service, ____ hot meals are delivered to elderly people who may not be able to move around very easily.
A．that
B．which
C．where
D．what
大豆的白花和紫花为一对相对性状，下列四种杂交实验中，能判定性状显隐性关系的是
①紫花×紫花→紫花 ②紫花×紫花→301紫花+101白花 ③紫花×白花→紫花 ④紫花×白花→98紫花+107白花[ ]
A．①和②
B．②和③
C．③和④
D．④和①
