Barometers and Open-Tube Manometers Are Two Instruments That Are Used

Multiple Choice

Barometers and open-tube manometers are two instruments that are used to measure pressure.Which statement is true?

A) Both measure gauge pressure
B) Both measure absolute pressure
C) Barometers measure gauge pressure and manometers measure absolute pressure
D) Barometers measure absolute pressure and manometers measure gauge pressure
E) Both measure an average of the absolute and gauge pressures