The Reliable Company makes industrial parts. The company is producing significantly below its capacity at present. The Erstwhile Company has made an offer to buy 40,000 parts from Reliable at $1.25 each. Reliable sells its parts wholesale for $1.40 each. The average cost per unit is $1.28, of which $0.15 is fixed cost. If Reliable were to accept Erstwhile's offer, what would be the increase in Reliables operating profit?

A. $2,400 B. $4,800 C. $3,600 D. $1,200