What causes the air pressure dial to move in an aneroid barometer? Group of answer choices

a Mercury inside the barometer rises and falls moving the dial according to the increase or decrease in pressure.

b Weights activated by air pressure change position according to the weight of the air moving a dial on the instrument.

c A spring inside the instrument, connected to a dial, moves when the air pressure contacts the spring.

d A small flexible metal box expands and contracts which is connected to the instrument's dial.