My mother is a village woman, that is already in her fifties. She has a little education, but she knows knowledge is of greatly importance to young people. She often asks me how I get along for my studies and encourages me study hard. My mother do everything she can for me so that I can spend more time on my studies. Once she was badly ill and had stayed in bed for several day. When I got home, I found the light was still on and my mother was sitting in bed, made new clothes for me! I was so deeply moving that tears came to my eyes. Such is my mother, a kind but hard-working woman.

螺杆式冷水机组的高压控制器失灵时，高压侧压力上升到（）为防止破坏性事故发生，安全阀自动起跳，将排出的高压制冷剂导入低压部分。

A.1.8MPa

B.2.3MPa

C.1.6MPa

D.0.8MPa