premise: Christopher has only visited Democratic Republic of the Congo, Chester has only visited Côte D'ivore, Ronnie has only visited Lesotho, Mark has only visited India, Raymond has only visited Barbados, Greg has only visited Moldova, Jonathan has only visited Djibouti, Byron has only visited Jamaica, Alfredo has only visited Sweden, Karl has only visited El Salvador, Francis has only visited Madagascar, Vincent has only visited Ukraine
hypothesis: Jonathan didn't visit Djibouti