Question: which sector of indian economy contributes largest of the gross national product
[{'answer': 'Services', 'provenance': [{'wikipedia_id': '1472206', 'title': 'Economy of India', 'start_paragraph_id': 38, 'start_character': 514, 'end_paragraph_id': 38, 'end_character': 522, 'bleu_score': 1.0, 'section': 'Section::::History.:Post-liberalisation period (since 1991).\n'}]}]