You Are a Sales Representative for Caterpillar, Inc

You are a sales representative for Caterpillar, Inc. You've got two customers who both want to purchase hydraulic shovels, which weigh in at just over 1,000 tons. One of these customers is located in Houston, Texas, not far from the manufacturing plant where the shovels will be made. The other is located in Rockport, Maine. What does the Robinson-Patman Act dictate about the prices you can ask for these two hydraulic shovels?

A) You are allowed to charge the Maine-based company more due to the higher cost of delivering the 1,000-ton shovel to its location.
B) You must charge the Texas-based company more because you are manufacturing and delivering the product within the same state.
C) You must charge the Maine-based company an additional tax due to interstate transportation.
D) It would be illegal price discrimination to charge either company more or less than the other.