A person’s psychosocial needs during the dying process of a relative may include

A. flexible visitation, participation in client care, and rest breaks.
B. flexible visitation, denial of imminent death, and rest breaks.
C. limited visitation, participation in client care, and rest breaks.
D. short, frequent, limited periods of visitation; participation in client care; and rest breaks.

下述各说法正确的是（）。

A．若质点对某定点的动量矩守恒，则其动量也一定守恒

B．若质点对某定点的动量矩守恒，则其动能一定为常量

C．若质点的动量改变，其动能也一定发生变化

D．若质点的动能发生变化，则其动量也一定发生变化