Under the Revised UCC Secured Transaction Article, which of the following statements is correct concerning the disposition of collateral by a secured creditor after a debtor’s default?

a. A good-faith purchaser for value and without knowledge of any defects in the sale takes free of any subordinate liens or security interests.

b. The debtor may not redeem the collateral after the default.

c. Secured creditors with subordinate claims retain the right to redeem the collateral after the collateral is sold to a third party.

d. The collateral may only be disposed of at a public sale.