有下列说法：

①平行四边形具有四边形的所有性质；

②平行四边形是中心对称图形；

③平行四边形的任一条对角线可把平行四边形分成两个全等的三角形；

④平行四边形的两条对角线把平行四边形分成4个面积相等的小三角形．

其中正确说法的序号是  [ ]

(A)①②④

(B)①③④

(C)①②③

(D)①②③④

The nurse is caring for a bedridden, elderly adult. To prevent pressure ulcers, which intervention should the nurse include in the care plan ？（）

A．Turn and reposition the client a minimum of every 8 hours.

B．Vigorously massage lotion into bony prominences.

C．Post a turning schedule at the client's bedside.

D．Slide the client, rather than lift, when turning.