premise: Ron has only visited Bosnia & Herzegovinia, Martin has only visited Somalia, Tracy has only visited El Salvador, Ronnie has only visited Central African Republic, Ralph has only visited Myanmar, Eric has only visited Tajikistan, Ray has only visited Venezuela, Nathaniel has only visited Italy, Oscar has only visited Saint Kitts & Nevis, Gilbert has only visited Syria, Charles has only visited Bangladesh, Hector has only visited Iceland
hypothesis: Ron didn't visit Bosnia & Herzegovinia