Read the following excerpt from a US court opinion:
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from antitrust liability under the Sherman Act and the Virgin Islands Anti-monopoly Law. Under Rule 56(c), this Court must accordingly grant defendant CAI’s motion for partial summary judgment. Celotex Corp. v. Catrett, 477 U.S. 317, 322-323, 106 S.Ct. 2548, 2552, 91 L.Ed.2d 265 (1986). B. Antitrust Liability Under The Sherman Act. CAI argues that VIPA is immune from antitrust liability under the Sherman Act as a result of the doctrine of governmental immunity. As defendant CAI correctly notes, virtually all levels of government have been granted some degree of immunity from the operation of antitrust law generally and the Sherman Act specifically. See Sea Land Service v. Alaska Railroad, 659 F.2d 243 (D.C.Cir.1981), cert. denied 455 U.S. 919, 102 S.Ct. 1274, 71 L.Ed.2d 459 (1982) ; Parker v. Brown, 317 U.S. 341, 63 S.Ct. 307,
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What is the most suitable continuation to the opinion? Your options are:
A. holding that a railroad owned and operated by the federal government was immune from antitrust action under the governmental immunity doctrine which protects the federal government its agencies and instrumentalities from the reaches of antitrust law
B. holding that an individual is immune from antitrust liability for exercising first amendment right to petition the government
C. holding that a railroad operated and owned by the federal government was immune from antitrust liability
D. holding federal credit unions to be government instrumentalities immune from state taxation
E. holding that there must be a causal connection between the alleged antitrust violation and the antitrust injury for there to be antitrust standing
Reply with [A, B, C, D, E] only.