Question: which group immigrated to the united states to work on the transcontinental railroads
[{'answer': 'Chinese', 'provenance': [{'wikipedia_id': '3612404', 'title': 'History of Chinese Americans', 'start_paragraph_id': 0, 'start_character': 11, 'end_paragraph_id': 0, 'end_character': 18, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]