Final answer:
By the year 2050, it is projected that one in two Americans could have African, Asian, Hispanic, or Native American ancestry, signifying a dramatic shift in the ethnic composition of the U.S. population.
Step-by-step explanation:
The question of how the ancestry composition of the United States will change by the year 2050 is rooted in analyses of population trends, including immigration, birth rates, and ethnographic projections. Based on information from the U.S. Census Bureau and other demographic research, it is projected that by 2050, a significant transformation in the nation's ethnic composition will take place. Specifically, a larger proportion of the population will identify as having African, Asian, Hispanic, or Native American ancestry.
The current estimation that nearly one in four Americans have such ancestry will evolve by 2050. By that time, projections suggest that a staggering one in two Americans could identify with these ancestries, reflecting the diverse and continually changing tapestry of the U.S. population. Such changes are attributed to a combination of factors including ongoing immigration patterns and different birth rates among various racial and ethnic groups, as well as the potential population booms in regions like Africa and India.
Therefore, in response to the student's question regarding the projected ancestry composition by 2050, the most accurate estimation from the provided options would be b) One in two.