Farmer grows grain on his farm in Nebraska for feed for the chickens that he raises on that same farm. He later sells the chickens to meat packing companies within the state of Nebraska. The production of grain on the farm:

A. Affects interstate commerce and, therefore, can be subject to federal regulation.

B. Only indirectly affects interstate commerce and, therefore, can be subject to state, but not federal, regulation.

C. Only indirectly affects interstate commerce, and thus is not subject to federal regulation under the commerce clause.

D. Directly affects intrastate commerce, but more indirectly affects interstate commerce and, therefore, can be subject to federal regulation under the commerce clause.