Robert Borrows $500 from a Pawn Shop,leaving His Class Ring

Robert borrows $500 from a pawn shop,leaving his class ring as collateral.Later,Robert borrows $200 from a bank.Robert signs a security agreement,later filed by the bank,giving the bank a security interest in this ring.If Robert defaults on both loans,who has superior rights to the ring?

A) the pawn shop, because it was the first security agreement to be formed
B) the pawn shop, because it was the first to perfect
C) the bank, unless the pawn shop's security agreement was in writing
D) the bank, because the pawn shop's interest is not perfected
E) the bank, because banks have priority over other creditors