Question: which enzyme seals the gap between the okazaki fragments
[{'answer': 'ligase', 'provenance': [{'wikipedia_id': '506315', 'title': 'Okazaki fragments', 'start_paragraph_id': 1, 'start_character': 196, 'end_paragraph_id': 1, 'end_character': 202, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]