Question

Boys develop a deeper voice than girls because their ______________ becomes bigger.

Answer 1

Voice is produced by a voice box which is called larynx and the growth of larynx starts during puberty in both boys and girls. There is growth of Adam’s apple seen in boys.

Complete answer:
When the kids hit puberty then their bodies and minds both go through many changes and there’s one change which every kid can count on i.e., the growth of body parts and changing shape. Every part gets into the growing action which includes larynx or you can call it voice box as voice box is another name for larynx.
Larynx is in the throat which gives you the voice whether you’re talking, laughing, whispering, singing, or shouting and when you touch your throat and humming, you will feel vibrations under your finger and that is the larynx.
During puberty, this larynx grows larger and it sticks out at the front of the throat which is called Adam's apple. Adam’s Apple sometimes looks small and rounded like an apple just under the skin in front of the throat.
Larynx grows in both girls and boys during puberty but a girl’s larynx does not grow as much as a boy’s larynx grows due to which boys have Adam’s apples whereas most girls do not have it. Due to this Adam’s apple in boys, they develop a deeper voice than girls.
Larger larynx also gives deeper voice to boys and girls voices get a little bit deeper as their larynx gets larger too but still boy’s larynx grows so much more than girls due to which they develop deeper voices than girls.

Therefore, Boys develop a deeper voice than girls because their voice box/larynx becomes bigger.

Note: During puberty, there is growth of body parts in both boys and girls. Voice is produced by a voice box which is known as larynx and it begins to grow during puberty but there is more growth seen in boys due to which they develop a deeper voice than girls.