With no explanation, chose the best option from "A", "B", "C" or "D". the defendant, are not to be counted. Also, sentences resulting from convictions that a defendant shows to have been previously ruled constitutionally invalid are not to be counted. U.S.S.G. § 4A1.2, comment, (n.6) (Nov.1990) (emphasis added). In addition, the Commission added Background Commentary to § 4A1.2 that provided, “The Commission leaves for court determination the issue of whether a defendant may collaterally attack at sentencing a prior conviction.” U.S.S.G. § 4A1.2, comment (backg’d.). .2d 63 (1992); United States v. Canales, 960 F.2d 1311, 1315 (5th Cir.1992) (same); United States v. Hoffman, 982 F.2d 187, 190 (6th Cir.1992) (same) and United States v. Brown, 991 F.2d 1162, 1166 (3d Cir.1993) (same) with United States v. Vea-Gonzales, 986 F.2d 321, 327 (9th Cir. 1993) (<HOLDING>); United States v. Roman, 989 F.2d 1117, 1119

A: holding amended language gives district courts discretion to permit collateral attack on prior convictions used to enhance sentence
B: holding that defendants sixth amendment right to trial by a jury was not violated by district courts reliance on his prior convictions for purposes of sentencing as career offender
C: holding that defendants sixth amendment right to trial by a jury was not violated by district courts reliance on his prior convictions for purposes of sentencing under the acca even though convictions were neither charged in indictment nor admitted
D: holding that commission did not intend amended language to provide discretion to district courts to entertain challenges to prior convictions at sentencing
D.