Which of the Following Best Defines a Proof of Claim

Which of the following best defines a proof of claim?

A) a statement by the debtor that states that he or she has debts
B) a document required to be filed by a debtor showing property that is exempt from constituting the bankruptcy estate
C) a document required to be filed by a creditor that states the amount of his or her claim against the debtor
D) a statement by creditors alleging that the debtor is not paying his or her debts as they become due