How often should air tanks be drained?

Answer: B — Once a day

Air tanks should be drained once a day to prevent the buildup of moisture. Moisture can accumulate in the air tanks due to condensation from the compressed air. If not drained regularly, this water can lead to problems, such as rust and corrosion of the tank and components, affecting the air brake system's reliability and performance. Daily draining helps ensure that any moisture is removed, maintaining the integrity of the air brake system and preventing potential brake failures or other operational issues.