Question

The Baby Boom coincided with

economic prosperity in the United States

a recession in the United States

a depression in the United States

high immigration to the United States

Answer 1

I believe it's " economic prosperity in the United States"

Answer 2

Source: http://www.valueoptions.com/spotlight_YIW/baby_boomers.htm
"During the late 1940s and early 1950s, post-war optimism inspired a sense of stability, opportunity and prosperity"