Question: which element present in green pigment of leaf
[{'answer': 'Chlorophyll', 'provenance': [{'wikipedia_id': '6985', 'title': 'Chlorophyll', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 11, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '6985', 'title': 'Chlorophyll', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 325, 'bleu_score': 0.7266665142929991, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6613019067708722513}, 'section': 'Section::::Abstract.'}]}]