Checks and balances is something where each branch has certain limitations so neither branch can become over powered hope this helps and have a wonderful day :)
well ...here is the answer
The United States Department of Homeland Security (DHS) is a federal agency designed to protect the United States against threats. Its wide-ranging duties include aviation security, border control, emergency response and cyber-security.
Answer:
B
Explanation:
unifying Korea under the Koryu dynasty