You negotiate a sale with a mill in which you sell them wheat at a basis of -10 MAR for Jan/Feb shipment picked up at your elevator (no freight). It is currently June (pre-harvest) and you have no ownership of wheat at this time. Having made this sale without currently owning wheat, which of these circumstances would be your best alternative to purchase the bushels?

a. Purchase wheat in Jan/Feb at +10 MAR and incur no cost-of-carry.
b. Purchase wheat in Jan/Feb at -25 MAR and incur no cost-of-carry.
c. Purchase wheat in August at -45 SEP and carry the bushels to deliver in Jan and Feb.
d. Spread SEP/MAR at 20¢ carry and incur 20¢ cost-of-carry