Question: who is the highest ranking officer in the us army
[{'answer': 'colonel', 'provenance': [{'wikipedia_id': '1516389', 'title': 'United States military seniority', 'start_paragraph_id': 3, 'start_character': 228, 'end_paragraph_id': 3, 'end_character': 235, 'bleu_score': 1.0, 'section': 'Section::::Modern-day seniority.\n'}]}, {'provenance': [{'wikipedia_id': '1516389', 'title': 'United States military seniority', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 1087, 'bleu_score': 0.9550159410945921, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 418103011429029246}, 'section': 'Section::::Modern-day seniority.\n'}]}]