With no explanation, chose the best option from "A", "B", "C" or "D". GM and OnStar requested summary judgment concerning the invalidity of the '743 patent. However, GM’s and OnStar’s request that the '743 patent be declared invalid was raised as a counterclaim. GM and OnStar asserted another declaratory judgment counterclaim in which they asked the court to declare the '743 patent unenforceable as a result of inequitable conduct in the prosecution of the patent. The Court of Appeals for the Federal Circuit has established that a district court has discretion to dismiss invalidity and unenforceability counterclaims upon a grant of summary judgment of non-infringement. Phonometrics, Inc. v. Northern Telecom Inc., 133 F.3d 1459, 1468 (Fed.Cir.1998); Cardinal Chemical Co. v. Morton Int'l, Inc., 508 U.S. 83, 95, , 495 F.3d 1340, 1347 (Fed.Cir.2007) (<HOLDING>). Thus, although it is unclear when a district

A: holding that district court correctly determined that it had been divested of jurisdiction to hear defendants counterclaims for invalidity and unenforceability when plaintiff had voluntarily dismissed its infringement claims without prejudice before trial
B: holding that the district court had discretion where plaintiff sought to amend a count that had been dismissed with prejudice
C: holding that district court erred in determining that jury verdict of noninfringement divested district court of jurisdiction to hear unenforceability counterclaim
D: holding that the circuit courts order concluding that it was without jurisdiction to entertain a complaint because the case had been dismissed without prejudice constituted a final order because all other claims either had been refiled or dismissed with prejudice
A.