Read the following excerpt from a US court opinion:
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failing to “properly investigate any avenues of defense” — other claims, such as the claim that counsel failed to move to suppress the drugs and failed to contact the owners of the building, present issues upon which the District Court could have proceeded. Furthermore, some of Mercer’s other claims, such as the claim that the prosecution had bribed Yians and Hart, are not the type of claims that Mercer could realistically support at this stage of the proceedings; while Mercer may well fail to meet his burden of proof on these claims, he alleged sufficient facts to withstand summary dismissal. Therefore, we believe that the District Court should consider anew the various grounds for relief, and dismiss only those grounds that are truly vague and conclusory. See Thomas, 221 F.3d at 437 . Accordingly, we will summarily vacate the
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What is the most suitable continuation to the opinion? Your options are:
A. holding that appellate court should overturn a district courts denial of a motion to amend a complaint only if the district court has abused its discretion
B. holding that the trial court had abused its discretion in dismissing the case without allowing appellants an opportunity to amend
C. holding that district court had not abused its discretion in denying plaintiffs motion to amend complaint
D. holding that the district court erred in summarily dismissing a  1983 complaint that should have been brought as a habeas petition
E. holding that the district court abused its discretion by summarily dismissing all 26 grounds in a  2255 motion where only certain claims were vague and conclusory
Reply with [A, B, C, D, E] only.