Question: The Isla Vizcaíno is an island in Uruguay located on the estuary of the Yaguarí creek, the northern arm of the estuary of the Río Negro (Uruguay) of which river in South America, that flows from north to south and forms parts of the boundaries of Brazil, Argentina, and Uruguay, separating some of the Argentine provinces of La Mesopotamia from the other two countries?
Sentence (from "Vizcaíno Island"): It is bordered by the South Black River on the East and the Vizcaíno creek to the east, the Uruguay River to the North and the Arroyo Yaguarí on the West.
Relevant evidence: No