Respuesta :
I believe the answer is: C.There are a Greater number of retirees in the system
The main duty of social security administration is to manage social insurance program that consist of retirement planning, disability compensation, and survivors' benefits.
Due to the development of health industry, people in united states have higher life expectancy, which is really good in a certain way, but it also create large amount of retirees that needed to be supported by the government.