Darrell Owns a Furniture Store

Darrell owns a furniture store. If he decided to expand the size of his store in order to sell more furniture, how would he know if he is experiencing diseconomies of scale?

A) His total cost of selling furniture decreases.
B) His average cost of selling furniture increases.
C) His total cost of selling furniture remains unchanged.
D) His average cost of selling furniture remains unchanged.
E) His average cost of selling furniture decreases.