Question: who is the original singer of i heard it through the grapevine
[{'answer': 'Gladys Knight & the Pips', 'provenance': [{'wikipedia_id': '1124294', 'title': 'I Heard It Through the Grapevine', 'start_paragraph_id': 1, 'start_character': 197, 'end_paragraph_id': 1, 'end_character': 221, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1124294', 'title': 'I Heard It Through the Grapevine', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 312, 'bleu_score': 0.9645876452711911, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4568634059941984207}, 'section': 'Section::::Abstract.'}]}]