Question: what type of stone is stonehenge made of
[{'answer': 'sarsen', 'provenance': [{'wikipedia_id': '27633', 'title': 'Stonehenge', 'start_paragraph_id': 22, 'start_character': 291, 'end_paragraph_id': 22, 'end_character': 297, 'bleu_score': 1.0, 'section': 'Section::::Early history.:Stonehenge 3 I (c. 2600 BC).\n'}]}, {'answer': 'bluestone', 'provenance': [{'wikipedia_id': '27633', 'title': 'Stonehenge', 'start_paragraph_id': 2, 'start_character': 244, 'end_paragraph_id': 2, 'end_character': 253, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]