Question: who is the railway minister of bihar in 2018
[{'answer': 'Piyush Goyal', 'provenance': [{'wikipedia_id': '23308780', 'title': 'Minister of Railways (India)', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 12, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]