What Is the Legal Significance of the Distinction Between Rule

What is the legal significance of the distinction between rule of reason violations and per se violations under the Sherman Act?

A) Rule of reason violations must be proven beyond a reasonable doubt,and per se violations must be proven with a preponderance of the evidence.
B) Rule of reason violations require an agreement with at least one other party,but per se violations can occur without an agreement with others.
C) Rule of reason violations relate to horizontal situations,and per se violations relate to vertical situations.
D) Rule of reason violations relate to actions brought by private parties,and per se violations relate to actions brought by the government.
E) Rule of reason violations might be proven to be acceptable,but per se violations cannot be acceptable under any circumstances.