Question: land conversion through burning of biomass releases which gas
[{'answer': 'carbon monoxide', 'provenance': [{'wikipedia_id': '7906908', 'title': 'Biomass', 'start_paragraph_id': 28, 'start_character': 381, 'end_paragraph_id': 28, 'end_character': 396, 'bleu_score': 1.0, 'section': 'Section::::Environmental impact.\n'}]}, {'answer': 'hydrogen', 'provenance': [{'wikipedia_id': '7906908', 'title': 'Biomass', 'start_paragraph_id': 5, 'start_character': 268, 'end_paragraph_id': 5, 'end_character': 276, 'bleu_score': 1.0, 'section': 'Section::::Biomass feedstocks.\n'}]}, {'answer': 'traces of methane'}]