Which river has the most water by volume?
{'directed': True, 'multigraph': False, 'graph': {}, 'nodes': [{'type': 'INTERNAL', 'name_': 'Q6173448', 'id': 0, 'label': 'Wikipedia:Vital articles/Level/4'}, {'type': 'INTERNAL', 'name_': 'Q5460604', 'id': 1, 'label': 'Wikipedia:List of articles all languages should have'}, {'type': 'QUESTIONS_ENTITY', 'name_': 'Q4022', 'id': 2, 'label': 'river'}, {'type': 'INTERNAL', 'name_': 'Q6388', 'id': 3, 'label': 'swimming'}, {'type': 'ANSWER_CANDIDATE_ENTITY', 'name_': 'Q10843402', 'id': 4, 'label': 'swimmer'}, {'type': 'INTERNAL', 'name_': 'Q180748', 'id': 5, 'label': 'Mark Spitz'}], 'links': [{'name_': 'P5008', 'source': 2, 'target': 0, 'label': 'on focus list of Wikimedia project'}, {'name_': 'P5008', 'source': 2, 'target': 1, 'label': 'on focus list of Wikimedia project'}, {'name_': 'P1889', 'source': 2, 'target': 2, 'label': 'different from'}, {'name_': 'P5008', 'source': 3, 'target': 1, 'label': 'on focus list of Wikimedia project'}, {'name_': 'P3095', 'source': 3, 'target': 4, 'label': 'practiced by'}, {'name_': 'P5008', 'source': 5, 'target': 0, 'label': 'on focus list of Wikimedia project'}, {'name_': 'P106', 'source': 5, 'target': 4, 'label': 'occupation'}]}