The correct answer is the following: option B. The use of the word dissuading reflects that Thurber disagrees with the decision his father made. The verb dissuade means the act to persuade someone not to do something. When Thurber says he could not dissuade his father from going into the attic, he is showing that he tried to make his father do the opposite of what he ended up doing. The author's word choice, in this case the word dissuading, shows the character's view on the action, in this case it reflected Thurber's feelings on what he dad chose to do.
