Seven States Have Adopted Some Form of a Fully-Funded "Clean

Seven states have adopted some form of a fully-funded "clean elections" campaign finance system. Which feature below is NOT generally included in those systems?

A) Candidates must obtain a set minimum number of signatures.
B) Candidates must raise a minimum number of dollars from a set number of donors.
C) Candidates may spend up to $50,000 of their own money.
D) Once qualified, candidates must only spend public funds.