Question: the tank was introduced by to the battlefields of world war i by
[{'answer': 'the British Army', 'provenance': [{'wikipedia_id': '2994067', 'title': 'Tanks in World War I', 'start_paragraph_id': 2, 'start_character': 216, 'end_paragraph_id': 2, 'end_character': 232, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2994067', 'title': 'Tanks in World War I', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 557, 'bleu_score': 0.977897140678983, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11601589876856638118}, 'section': 'Section::::Abstract.'}]}]