Vocal cords produce sound when air from the lungs pushes past them, causing them to vibrate. The girl in the image below is using her vocal cords to produce sounds known as singing.
What does the girl need to do to increase the volume of her voice?
A.
contract her throat muscles in order to tighten her vocal cords
B.
relax her throat muscles in order to loosen her vocal cords
C.
decrease the force with which air is traveling past her vocal cords
D.
increase the force with which air is traveling past her vocal cords