Question: neutrons that combined with protons in an atomic nucleus early in the universe's history form
[{'answer': 'hydrogen ( hydrogen - 1'}, {'answer': 'the hydrogen isotope deuterium ( H or D )'}, {'answer': 'the helium isotope helium - 3 ( He )'}, {'answer': 'lithium isotope lithium - 7 ( Li )'}, {'answer': 'helium as the isotope helium - 4 ( He )'}, {'provenance': [{'wikipedia_id': '44058', 'title': 'Big Bang nucleosynthesis', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 1073, 'bleu_score': 0.8331862476396991, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8963366079976760051}, 'section': 'Section::::Abstract.'}]}]