Please mark the only INCORRECT statement about FX and Interest Rate Swaps

a. For both FX and interest rate swaps, from the begining until the end of the contract, the NPV for both parties in the contract will ALWAYS remain constant

b. Interest rate swaps allow firms to shift their interest rate exposure from fixed to floating rates or vice versa

c. Interest rate swaps allow firms to manage their interest rate risk or to speculate on the direction of interest rates

d. In an interest swap contract, the notional principal is the amount of the outstanding debt in the contract