施工合同实施偏差分析的内容包括，产生合同偏差的原因分析，合同实施偏差的责任分析以及（ ）。

A．不同项目合同偏差的对比

B．偏差的跟踪情况分析

C．合同实施趋势分析

D．业主对合同偏差的态度分析

When assessing a client as a candidate for crutch walking, the nurse should take into account that for some elderly people, crutch walking is an impractical goal primarily because which of the following reason（）

A. Decreased reaction time.

B. Decreased visual acuity.

C. Decreased motor coordination.

D. Decreased level of comprehension.