'Person who pilots or travels in a balloon, airship or other aircraft' is called Aeronaut, Option A. Option B, 'Astronaut' is a person who is trained to travel in a spacecraft. Option C, 'Aerobats' are spectacular stunts, such as rolls and loops, performed in an airplane or glider. Option D, 'Acrobat' is an entertainer who performs gymnastic feats. Thus., options B, C and D are incorrect options and the correct word for the given phrase is Option A, 'Aeronaut'.