Question: which is the major limiting element in marine primary production
[{'answer': 'the availability of light', 'provenance': [{'wikipedia_id': '208303', 'title': 'Primary production', 'start_paragraph_id': 16, 'start_character': 432, 'end_paragraph_id': 16, 'end_character': 457, 'bleu_score': 1.0, 'section': 'Section::::Oceanic production.\n'}]}, {'answer': 'mineral nutrients', 'provenance': [{'wikipedia_id': '208303', 'title': 'Primary production', 'start_paragraph_id': 12, 'start_character': 281, 'end_paragraph_id': 12, 'end_character': 298, 'bleu_score': 1.0, 'section': 'Section::::Terrestrial production.\n'}]}, {'provenance': [{'wikipedia_id': '208303', 'title': 'Primary production', 'start_paragraph_id': 16, 'start_character': 0, 'end_paragraph_id': 16, 'end_character': 816, 'bleu_score': 0.96401701927018, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12531081820030101168}, 'section': 'Section::::Oceanic production.\n'}]}]