Why Is Social Security Often Called the "Third Rail" of American

Why is Social Security often called the "third rail" of American politics?

A) because politicians' attempts to reform Social Security have fierce electoral consequences
B) because Social Security was the third major social welfare program created in the American political system
C) because Social Security is one of three universal welfare programs
D) because the program is among the three most popular social welfare programs in the country
E) because benefits are received during the third portion of a person's life