Which of the Following Is True

Which of the following is true?

A) The merger between Exxon and Mobil was subject to antitrust regulation by the U.S.Justice Department,but not by the European Commission.
B) Antitrust today could best be summed up by the 90 percent rule.
C) In the 1950s and 1960s the predominant types of mergers were of the conglomerate variety.
D) When two firms in the same industry form one larger company it is called a vertical merger.