Read the following excerpt from a US court opinion:
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questions sought to be raised can be the subject of controversy.” Goosby, 409 U.S. at 518, 93 S.Ct. 854. In other instances, the Supreme Court has described insubstantial claims as “so attenuated and unsubstantial as to be absolutely devoid of merit,” “wholly insubstantial,” “obviously frivolous,” and “no longer open to discussion.” Hagans v. Lavine, 415 U.S. 528, 536-38, 94 S.Ct. 1372, 39 L.Ed.2d 577 (1974) (collecting cases) (citations and internal quotation marks omitted). The Supreme Court has suggested that this standard is rarely met. See Hagans, 415 U.S. 528, 94 S.Ct. 1372; Goosby, 409 U.S. 512, 93 S.Ct. 854. Our limited treatment of the “insubstantial” standard makes use of similar language. See Loeber v. Spargo, 144 Fed.Appx. 168, 170 (2d Cir.2005) (unpublished summary order) ; Green, 380 F.2d at 448 (stating that a claim
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What is the most suitable continuation to the opinion? Your options are:
A. holding that the taxpayer filed a frivolous return because it had no basis in law or fact
B. holding defendant may receive only the portion of his fees under 42 usc  1988 that he would not have paid but for the frivolous claim
C. holding that a claim is insubstantial only if prior decisions render the issue inescapably frivolous and leave no room for any inference of controversy
D. holding trial courts finding that claim was frivolous insufficient to meet statutory requirement that claim constitutes harassment is groundless and not made in good faith
E. holding that in context of patent claim at issue if means only if
Reply with [A, B, C, D, E] only.