Both questions would be the last answer choice because a denotation of "baby boom" is a temporary marked increase in the birth rate, especially the one following World War II, and after the World War II, MANY people lost a lot of money due to their donations to help their soldiers, and since the soldiers have done their hard work for their country, the U.S. cut some prices on things for them because of their task. ;-)
I hope I helped! =D