Question: what is the fourth largest country in south america
[{'answer': 'Colombia', 'provenance': [{'wikipedia_id': '47668146', 'title': 'List of South American countries by area', 'start_paragraph_id': 5, 'start_character': 129, 'end_paragraph_id': 5, 'end_character': 137, 'bleu_score': 1.0, 'section': 'Section::::Transcontinental countries.\n'}]}]