What is the gauge manifold made of

I think it is.. the low side handwheel is made of blue plastic or occasionally has a blue decal in its center  then the high side handwheel is made of red plastic or occasionally has a red decal gauges used with a refrigeration gauge manifold are either analog which resemble other pressure gauges or perhaps digital i hope this helps :)

The answer is b; as a lab tech, you’re more behind the scenes and don’t interact with the patients.