Which of the Following Is a Correct Statement About Commerce

Which of the following is a correct statement about commerce power in the U.S.?

A) The power to regulate commerce is an enumerated power of Congress.
B) The Constitution does not delineate the dividing line between interstate commerce and intrastate commerce.
C) The Supreme Court has ruled that manufacturing is part of intrastate commerce and thus subject to state regulation only.
D) Congress invoked the commerce power in passing a federal law that prohibited the possession of guns within one thousand feet of a school.
E) All these answers are correct