I don't understand II

新东方老书section 7

17. The Gorton-Dodd bill requires that a bank disclose to their customers how long they will delay access to funds from deposited checks.

(A) that a bank disclose to their customers how long they will delay access to funds from deposited checks

(B) a bank to disclose to their customers how long they will delay access to funds from deposited check

(C) that a bank disclose to its customers how long it will delay access to funds from a deposited checks

(D) a bank that it should disclose to its customers how long it will delay access to funds from a deposited check

(E) that banks disclose to customers how long access to funds from their deposited check is to be delayed

Key is C, but C has a word like "a deposited checks". Why this is correct? Thanks again!