If a source radiates sound uniformly in all directions and you triple your distance from the sound source, what happens to the sound intensity at your new position?

a. the sound intensity drops to 1 / 27 of its original value. b. the sound intensity increases to three times its original value. c. the sound intensity drops to 1 / 3 of its original value. d. the sound intensity drops to 1 / 9 of its original value. e. the sound intensity does not change.