Read the following excerpt from a US court opinion:
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on the agreement rather than on the judgment.” Indeed, the instant Separation Agreement provides that "this Agreement shall independently remain in full force and effect, and shall survive any decree, order, or judgment hereafter entered and shall forever be binding and conclusive upon the parties.” Thus, under settled Virginia law, Hildebrand may properly sue under the Separation Agreement given that it was not merged in the Final Decree of Divorce. Id. 15 . As noted supra, both Hildebrand and Iron Works are citizens of Virginia, while Lewis is a citizen of Florida. 16 . It is axiomatic that subject matter jurisdiction can be challenged at any time, either by the parties or by the court sua sponte. See Rule 12(h)(3), Fed.R.Civ.P.; Lovern v. Edwards, 190 F.3d 648, 654 (4th Cir.1999)  (citations omitted). 17 . In this regard, it
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What is the most suitable continuation to the opinion? Your options are:
A. holding that state law claims cannot pend from a federal one over which the district court lacks subject matter jurisdiction
B. recognizing that a federal court is obliged to dismiss a case whenever it appears the court lacks subject matter jurisdiction
C. holding that when an appellate court determines that it lacks jurisdiction the only thing it can do is dismiss the appeal
D. recognizing that there are nonconstitutional grounds on which we may dismiss a suit before considering the existence of federal subject matter jurisdiction and concluding that the court could dismiss for failure to satisfy the demand pleading requirement of rule 231 before addressing subject matter jurisdiction
E. holding that a federal court is obliged to determine its own jurisdiction for each case
Reply with [A, B, C, D, E] only.