Which of the Following Would Support a Justification for a Government

Which of the following would support a justification for a government corporation?

A) The U.S.Postal Service is more efficient than private companies at delivering the mail.
B) The U.S.Postal Service is less efficient than private companies at delivering the mail.
C) The Tennessee Valley Authority provides energy because it would be difficult for private firms to make a profit supplying energy.
D) Amtrak trains are less efficient than private sector trains.
E) Amtrak trains are more costly than private sector trains.