What Was the Core Purpose of Agencies When They Were

What was the core purpose of agencies when they were first created?

A) To create a new government entity exclusively devoted to monitoring a particular area of activity.
B) To ensure the legislatures were not overstepping their constitutional authority.
C) To provide additional checks and balances on legislative power since the court wasn't reigning in the legislature.
D) To protect the rights of businesses in order to bolster commerce.