D - Hansel and Gretel must find a way to escape from the witch.
While answer A shows a conflict, their major conflict is with the witch. B is incorrect and they don't have any decision to make whether or not to stay and C is never mentioned in the text.
A. Sir Marhaus was killed and Sir Tristram was seriously wounded. In order to free his uncle King Mark of Cornwall, Tristan fought Sir Marhaus in a duel. Tristan was 18 whereas Marhaus was much older at the time of the duel. The faster Tristan won the duel but was wounded by Marhaus who used a poisoned spear during the fight and went to Ireland to be healed.
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