Right option is (b) Dry gases
For explanation: Our body is made of almost 60% of water and maintaining the water balance in the body is important. The lining of the respiratory tract contains mucus to trap any unwanted particles in the air. Even the lungs contain some percentage of water in form of moisture to better facilitate the exchange of gases in the body. Thus, when the air that is sent into the body has a low moisture content, it starts taking in moisture from the body which in the long run can desiccate the cells and cause bleeding. This causes the lung compliance the fall as well.