Question: who was prime minister of india in 1991
[{'answer': 'Chandra Shekhar', 'provenance': [{'wikipedia_id': '844745', 'title': 'List of Prime Ministers of India', 'start_paragraph_id': 3, 'start_character': 207, 'end_paragraph_id': 3, 'end_character': 222, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'P.V. Narasimha Rao'}, {'provenance': [{'wikipedia_id': '844745', 'title': 'List of Prime Ministers of India', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 954, 'bleu_score': 0.7803580047446981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16685680222345714101}, 'section': 'Section::::Abstract.'}]}]