A. Rise in the birth rates.
Step-by-step explanation:
After World War II, there was a massive rise in the birth rates, these people today are now called "baby boomers." Since there was a drastic rise in the birth rates, there needed to be more housing for the veterans, along with their increasingly large families. Levittown was just one of the many suburban places that mass-produced houses, that were affordable and contained many homes.