The correct answer is - Greece is bordered by land on one side only.
Greece is a country that has the territory in the shape of a mini peninsula, surrounded by water on three sides, and being connected with the land only on one side, the northern side.
The territory of Greece had always been in the southern part of the Balkan Peninsula, and it also includes thousands of islands in its territory. Unlike the ''popular'' belief that the Greeks managed to enlarge their territory and not be restricted to this part only, in fact they never did, it was the Macedonians that did, but they combined their culture with the Greek one, thus the confusion.
Greece only managed to expand its territory further north by occupying the territory of Aegean Macedonia and Thrace after World War II.
