Question: which elements are primarily involved in the suns fusion reaction
[{'answer': 'hydrogen', 'provenance': [{'wikipedia_id': '21544', 'title': 'Nuclear fusion', 'start_paragraph_id': 2, 'start_character': 575, 'end_paragraph_id': 2, 'end_character': 583, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'helium', 'provenance': [{'wikipedia_id': '21544', 'title': 'Nuclear fusion', 'start_paragraph_id': 2, 'start_character': 588, 'end_paragraph_id': 2, 'end_character': 594, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '21544', 'title': 'Nuclear fusion', 'start_paragraph_id': 7, 'start_character': 0, 'end_paragraph_id': 7, 'end_character': 637, 'bleu_score': 0.981898582188057, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 18158821349855910784}, 'section': 'Section::::Process.\n'}]}]