临床多发性骨髓瘤最重要的死因是()
A．骨质损害
B．脑血管意外
C．反复严重感染和肾衰竭
D．贫血
E．心功能衰竭
参考答案：C
For everyone's safety, we _______ a1ways remember the law against driving after drinking. [ ]
A. could
B. should
C. might
D. would
在深度为5的满二叉树中，叶子结点的个数为 ______。
A．32
B．31
C．16
D．15
