In an Antitrust Case Where a Plaintiff Is Challenging a Proposed

In an antitrust case where a plaintiff is challenging a proposed merger involving the defendant (who wants the merger to be approved,) which of the following is true about the likely arguments the parties will make regarding the relevant market?

A) Any arguments are usually pointless, because relevant markets are usually clearly determined in advance.
B) Both parties will likely argue for a narrowly-defined relevant market.
C) The plaintiff will argue for a narrowly-defined relevant market, and the defendant will argue for a broadly-defined relevant market.
D) The plaintiff will argue for a broadly-defined relevant market, and the defendant will argue for a narrowly-defined relevant market.
E) Both parties will argue for a broadly-defined relevant market.