Read the following excerpt from a US court opinion:
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ing water right to acres put into irrigation within first years of appropriation)). Walton III allowed Walton to irrigate the 30 acres put into irrigation by his predecessors, but found that a delay of 23 years was not appropriation within a reasonable time, for the remaining acreage. Id. The parties generally agree that under Walton III the Court may look to Washington law for guidance in determining whether a non-Lummi has exercised due diligence to perfect a Winters right transferred with the sale of allotted lands. E.g. Lummi Brief, docket no. 718, at 32 (“Washington law provides guidance for a determination of reasonable diligence and suggests that a successor must put water to use within fifteen years of the parcel leaving Indian ownership.”); see also Walton III, 752 F.2d at 400 . Plaintiff United States suggests that under
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What is the most suitable continuation to the opinion? Your options are:
A. holding the court may look to state law for guidance where federal law is not fully developed
B. holding that in diversity cases federal courts are to apply state substantive law and federal procedural law
C. holding that the plaintiffs state law claims are preempted by federal law
D. holding that federal courts presiding over causes of action created by state law should apply state substantive law but federal procedural law
E. holding that a federal court may resort to state law analogies for the development of a federal common law of privileges in instances where the federal rule is unsettled
Reply with [A, B, C, D, E] only.