Answer:
(C) The growing power of the federal government in the wake of 9/11.
Explanation:
The Department of Homeland Security is a cabinet of the U.S. federal government created by the executive branch, and with the passing of the Homeland Security Act by Congress in 2002, with one of thier main purposes being fighting off terrorist attacks similiar to the ones commited in 9/11.
The creation of this department is an extension of the federal government as a tool to operate in matters concerning foreign individuals crossing American land, not only terrorism, but also border security and immigration.