Answer:
a. Members of the highest class in the U.S. are successfully maintaining their status.
Step-by-step explanation:
The popular belief is that America is a land for opportunities is commonly portrayed in the "American dream", yet several studies have demonstrated that US income inequality has steadily sharpened and social mobility is limited.
In 2008 studies showed that socioeconomic mobility in the U.S. had occurred from 1950 to 1980 and thereafter it declined substantially.
In 2013 reports indicated that income inequality was felt and became a permanent feature that reduced possibilities for higher social mobility.
So contrary to the notion that is often portrayed in the films and the media, US wealth is significantly at the hands of top 10 of American wealthiest families, and children from other families are likely to born at low income households.
Aditionally they are managig it well to remain in their condition of privilege, with a status at the cost of the remaining population.
The billionaries often are over the age of 60 and have at least one child which means they transmit their wealth and wealth is inherited with aims to preserve and increase it.
The consequences of this imply that Americans or people coming to the US from humble origins and getting rich is not as frequent as it occurred in the decades mentioned above.