As citizens of the United States, we are all free and capable of voicing our opinions. There are many ways in which citizens may attempt to influence their government's decisions on public policy matters. The best way to affect or change a policy at the national level would be to
A. write an editorial for the newspaper.
B. discuss the issue with the city council.
C. propose a solution to the state.
D. write a letter to a U.S. congressperson.