U.S. Code Title 18 § 1696 States

U.S. Code Title 18 § 1696 states
Whoever establishes any private express for the conveyance of letters or packets, or in any manner causes or provides for the conveyance of the same by regular trips or at stated periods over any post route which is or may be established by law, or from any city, town, or place to any other city, town, or place, between which the mail is regularly carried, shall be fined not more than $500 or imprisoned not more than six months, or both.
The Code of Federal Regulation (CFR) Title 39 Section 310.2 states
It is generally unlawful under the Private Express Statutes for any person other than the Postal Service in any manner to send or carry a letter on a post route or in any manner to cause or assist such activity. Violation may result in injunction, fine or imprisonment or both and payment of postage lost as a result of the illegal activity.
Under these laws, the U.S. Postal Service ________.

A) has a monopoly power over private express mail
B) has a comparative advantage over private express mail
C) competes in an oligopoly market for private express mail
D) competes in a monopolistic competition against other private express mail carriers