Final answer:
a. 1995 Lobbying Disclosure Act.
The most significant recent effort to limit lobbyists was the Honest Leadership and Open Government Act of 2007, which introduced strict regulations on campaign contributions and defined restrictions for recently retired government officials entering the lobbying industry.
Step-by-step explanation:
Regulation of Lobbyists
The most substantial attempt to curtail the influence of lobbyists in recent years was the Honest Leadership and Open Government Act of 2007. This act placed tighter restrictions on campaign contributions through PACs, on campaign travel and adjusted definitions of what constitutes a lobbyist. It also enacted "revolving door bans," requiring elected officials to wait at least one year before joining a lobbying firm post-service and limited the monetary value of gifts lobbyists can receive.
The Lobbying Disclosure Act of 1995 also played a vital role in regulating lobbying activities. It required lobbyists and interest groups to register with the federal government and provided a broadened definition of a lobbyist, ensuring detailed disclosure of lobbying activity, including targets and bills of interest.
Transparency in lobbying efforts is further enhanced by disclosure requirements mandating public knowledge of contribution sources. Such transparency is considered crucial in deterring lawmakers from aligning with controversial donors and in bolstering public awareness.