John Is a Successful Salesperson,but His Brother Has Always Had

John is a successful salesperson,but his brother has always had difficulty paying his bills.His brother wants to borrow some money from a bank,but the bank will not lend the money unless John will orally guarantee to repay the loan if his brother cannot.John does so.John's guaranty to repay is:

A) enforceable, because in general, guaranty contracts do not need to be in writing.
B) unenforceable, because in general, guaranty contracts need to be in writing.
C) enforceable, because the main purpose of the loan and the guarantee was to benefit John.
D) unenforceable, because his brother did not sign any agreement.
E) enforceable only if the bank can show that John had guaranteed debts for the brother before and paid them without a written document being in place.