Final answer:
The air gets from the nasopharynx to the middle ear through the eustachian tubes.
Step-by-step explanation:
The air gets from the nasopharynx to the middle ear via the eustachian tubes. The eustachian tubes are small passages that connect the nasopharynx to the middle ear, allowing for the equalization of pressure across the eardrum. When a diver needs to equalize the pressure in the middle ear, they can blow air into the nasopharynx, which then travels through the eustachian tubes and reaches the middle ear.