![](https://cos-cdn.shuashuati.com/pipixue-web/2020-1231-2005-12/ti_inject-812ce.png)
Which description about the wafers installed in the ALT is right?
A.
A higher pressure presses down on the wafers and causes them to collapse.
B.
A lower pressure allows the wafers to expand.
C.
A mechanical linkage connects the wafer movement to the needles on the indicator face, which translates compression of the wafers into a decrease in altitude and translates an expansion of the wafers into an increase in altitude.
D.
All the description above is right.