The nurse is teaching a client with chronic bronchitis about breathing exercises. Which of the following should the nurse include in the teaching

A．Make inhalation longer than exhalation.

B．Exhale through an open mouth.

C．Use diaphragmatic breathing.

D．Use chest breathing.

袖山高与袖肥分别近似于袖孔的纵向和横向直径，决定了袖孔的围度与形状，在袖孔围度不发生变化的情况下，袖山与袖肥的关系是（）。

A.正比例关系

B.反比例关系

C.无直接关系

D.两者相等