Answer:
C) The entrepreneur should definitely start the new business because his variable cost per pack of dough is already lower than that of the incumbent bakery.
Explanation:
The entrepreneur's average cost ($7) is equal to the incumbent bakery' variable cost ($7). As long as the customers are willing to pay at least $7 for the entrepreneurs cookie dough, he should start his business. This way marginal revenue ($7) = marginal costs ($7).