.The only sentence that contains a parallel structure is option B. Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal
Options A,C and D are not ´parallel structures because they do not carry the same tense
Parallel structure means that the items included in a list must be in the same form, in this case all main verbs are in the past simple
The technique that the poet use to communicate the speakers critical attitude towards war in the story is letter B. Kaspar repeatedly refers to the famous batle but admits that he cannot recall why it was fought. I hope you are satisfied with my answer.