Question: which category of food provides the most riboflavin
[{'answer': 'eggs', 'provenance': [{'wikipedia_id': '26229', 'title': 'Riboflavin', 'start_paragraph_id': 1, 'start_character': 119, 'end_paragraph_id': 1, 'end_character': 123, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'green vegetables', 'provenance': [{'wikipedia_id': '26229', 'title': 'Riboflavin', 'start_paragraph_id': 1, 'start_character': 125, 'end_paragraph_id': 1, 'end_character': 141, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'milk', 'provenance': [{'wikipedia_id': '26229', 'title': 'Riboflavin', 'start_paragraph_id': 1, 'start_character': 143, 'end_paragraph_id': 1, 'end_character': 147, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'meat', 'provenance': [{'wikipedia_id': '26229', 'title': 'Riboflavin', 'start_paragraph_id': 1, 'start_character': 173, 'end_paragraph_id': 1, 'end_character': 177, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '26229', 'title': 'Riboflavin', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 165, 'bleu_score': 0.7063511896022441, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 833550065044783130}, 'section': 'Section::::Abstract.'}]}]