Read the following excerpt from a US court opinion:
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1112, 1119 (5th Cir.1987) (“If a prisoner challenges a single hearing as constitutionally defective, he must first exhaust state habeas remedies.”); Alexander v. Ware, 714 F.2d 416, 419 (5th Cir.1983) ("If a prisoner challenges a 'single allegedly defective [disciplinary] hearing,’ he attacks, in essence, the fact and duration of his custody.’’). In such cases, we have required prisoners to exhaust the TDCJ grievance procedures. See Baxter v. Estelle, 614 F.2d 1030, 1031-32 (5th Cir.1980) ("[A] federal court may not grant ha-beas corpus relief to a petitioner who has failed to exhaust all administrative remedies, including an appeal to the Director of Corrections.”), cert. denied, 449 U.S. 1085, 101 S.Ct. 873, 66 L.Ed.2d 810 (1981); Lerma v. Estelle, 585 F.2d 1297, 1299 (5th Cir.1978) , cert. denied, 444 U.S. 848, 100 S.Ct. 95, 62
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What is the most suitable continuation to the opinion? Your options are:
A. holding that a prisoner exhausted his administrative remedies even though his grievance was untimely
B. holding that if adequate administrative remedies are available it is improper to seek relief in court before those remedies are exhausted
C. holding that a texas prisoner who had not exhausted his clearly available administrative remedies was properly denied habeas relief in the district court
D. holding that the prisoner has the burden of demonstrating he has exhausted his administrative remedies in his complaint
E. holding that administrative remedies must be exhausted prior to filing a claim in court
Reply with [A, B, C, D, E] only.