Question: what are two types of crust on the earths surface
[{'answer': 'continental', 'provenance': [{'wikipedia_id': '145700', 'title': 'Crust (geology)', 'start_paragraph_id': 3, 'start_character': 93, 'end_paragraph_id': 3, 'end_character': 104, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'oceanic', 'provenance': [{'wikipedia_id': '145700', 'title': 'Crust (geology)', 'start_paragraph_id': 3, 'start_character': 115, 'end_paragraph_id': 3, 'end_character': 122, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]