The correct answer is D. The diagram would be this:
-Lobbying scandals lead to calls for increased regulation.
-Congress passes the Honest Leadership and Open Government Act.
-Lobbysts have to file more detailed and frequent reports of their activities, pay, and expenses.
This law, enacted on September 14, 2007, came to impose greater restrictions on the lobbying activity in US politics, reinforcing certain measures aimed at transparency of parliamentary decisions, and prohibiting certain types of gifts to members of Congress.