At Rest,the Volume of Air in the Lungs Is 615

At rest,the volume of air in the lungs is 615 mL at 760 mm Hg. When the volume of the lungs expands during inhalation,what happens to the pressure inside the lungs?

A) The pressure inside the lungs decreases,which draws air into the lungs.
B) The pressure inside the lungs increases,which forces air inside the lungs.
C) The pressure inside the lungs remains constant,and air readily flows into the lungs.
D) The pressure inside the lungs cannot be determined if the weight of the person is unknown.