Answer:
A. Twenty years
Explanation: The Great Pyramid in Giza is considered to be a great work of architecture, where the whole construction, despite the simple tools of that time, is perfectly built. It consists of 2,300,000 stone blocks each of which weighs 2.5 tons. According to the writings of Greek historian Herodotus, it took twenty years to build the pyramid, and 100,000 slaves participated in its construction. It represents the only remaining, of the seven world wonders of the ancient world.
