Issues Such as the Environment, Health Care, Retirement Benefits, and Taxation

Issues such as the environment, health care, retirement benefits, and taxation are on the political agenda in the United States because

A) these are the only issues that are important to all Americans.
B) these are the only problems that have yet to be solved by the free market.
C) contemporary political parties mainly compete for the support of middle-class Americans and these issues are important to the middle class.
D) the Constitution limits the federal government's powers to legislating on these issues.
E) these are the only issues where Democrats and Republicans consistently agree with each other.