The correct answer is C) Mountain ranges made transportation very difficult.
The major difficulty with trade in ancient Greece was that mountain ranges made transportation very difficult.
Although trade was very important for the Greeks, its geographical characteristics made it difficult to trade by land. The geography of Greece has many mountain ranges. For instance, the Olympus range, a series of mountains, that includes the famous Olympus Mountain, home of the Greek gods in Greek Mythology. Another two mountain ranges in Greece are the Pindus range and the Rhod**e range. That is why the Greeks had a very good navy, not only for war purposes but also for trade by sea.
