Read the following excerpt from a US court opinion:
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of the evidence____” Section 3731 prior to amendment did not speak to the level of proof. However, the United States Court of Appeals for the Sixth Circuit in construing the False Claims Acts required that allegations in a civil action be proven by showing “specific intent to defraud” the United States by “clear, unequivocal, evidence.” United States v. Ekelman & Associates, Inc., 532 F.2d 545, 548 (6th Cir.1976); United States v. Ueber, 299 F.2d 310, 314-15 (6th Cir.1962). While federal appellate courts are yet to address the issue of retroactive application of the 1986 amendments to the False Claims Act, other federal district courts have reached differing conclusions on the issue. See United States ex rel. Boisvert v. FMC Corporation, No. 86020163 (N.D.Cal. September 9, 1987) ; United States v. Bekhrad, 672 F.Supp. 1529
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What is the most suitable continuation to the opinion? Your options are:
A. holding that only the amendments listed in  lb110c may be applied retroactively using a  3582e2 motion
B. holding that the protect act amendments to the standard of review apply retroactively
C. holding generally that new rules of law should not be applied retroactively in habeas corpus cases
D. holding that only the amendments listed in  lb110c may be applied retroactively using a  3582c2 motion
E. holding that the 1986 amendments may not be applied retroactively to cut off a defense which existed under the old law
Reply with [A, B, C, D, E] only.