The correct answer is D. Panama was an important route by which the treasures of the Incas's were transferred to Spain.
The Colonial Transisthmian Route of Panama was a land interchange between the Atlantic and the Pacific oceans across Central America. Spanish trading system crossed Panama in what was known as the “Intercontinental Royal Road”, during the 16th to the 19th centuries.
The Colonial Transisthmian Route of Panamá connected Panama to regions such as Spain, Canarias Islands, and the Caribbean.
