This question is pretty hard, as it deals with the genus of the fish mentioned above. Although it is called a trout, rainbow trout (Oncorhynchus mykiss) belong to the genus Oncorhynchus, as do Chinook salmon (Oncorhynchus tshawytscha) and Coho salmon (Oncorhynchus kisutch). Atlantic salmon (Salmo salar) are in the same family (Salmonidae), but belong to a different genus (Salmo).

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