Question: what ion drives the membrane potential back to resting membrane potential (repolarization)
[{'answer': 'K ions', 'provenance': [{'wikipedia_id': '1241864', 'title': 'Repolarization', 'start_paragraph_id': 1, 'start_character': 344, 'end_paragraph_id': 1, 'end_character': 350, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1241864', 'title': 'Repolarization', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 470, 'bleu_score': 0.777742218889497, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3806452920141839780}, 'section': 'Section::::Abstract.'}]}]