Read the following excerpt from a US court opinion:
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wide-ranging deference in the adoption and execution of policies and practices that in their judgment are needed to preserve internal order and discipline and to maintain institutional security.” Bell v. Wolfish, 441 U.S. 520, 547, 99 S.Ct. 1861, 60 L.Ed.2d 447 (1979). In this case, plaintiff claims that prison officials filed misconduct charges against him to retaliate for filing a lawsuit forcing the DOC to recognize the NOI as a religious group as well as filing grievances alleging violations of his First Amendment free exercise rights. Because both filing a lawsuit and filing grievances are protected activities, see Anderson v. Davila, 125 F.3d 148, 161 (3d Cir.1997) (finding that the filing of a lawsuit is protected activity); Herron v. Harrison, 203 F.3d 410, 415 (6th Cir.2000) ; Rivera v. Chesney, 1998 WL 639255, *1
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What is the most suitable continuation to the opinion? Your options are:
A. holding no first amendment right to file frivolous grievances
B. recognizing that prisoners undoubtedly exercise first amendment petition right when filing grievances and stating that prison officials may not retaliate against prisoners for filing grievances
C. recognizing first amendment petition right where inmate alleged retaliation for filing grievances
D. holding that an inmate has a first amendment right to file grievances against prison officials
E. holding that summary judgment was improper where genuine issues of material fact existed as to whether prison officials prevented inmate from filing grievances
Reply with [A, B, C, D, E] only.