John and Henry Go to the Bank So That Henry

John and Henry go to the bank so that Henry can borrow $50 000.00.The bank will only give Henry the money if John guarantees it,and John agrees in writing to do this.A couple of months later and unknown to John,Henry and the bank agree to material changes to Henry's loan,including increasing the interest rate substantially.If Henry defaults on the loan and the bank decides to sue both Henry and John

A) John's guarantee and Henry's debt are discharged by the changes made to the loan.
B) John will be held liable on his guarantee,but Henry will not be because of the material changes to the loan.
C) John,as guarantor,will be held liable on his guarantee,and Henry,as principal debtor,will be held liable on the debt.
D) John's guarantee is discharged due to the changes made to the loan,and the bank can only sue Henry on the debt.
E) none of the above