Who built the pyramids? the pyramids of egypt are truly an amazing sight. the tallest, known as the great pyramid, was close to 500 feet tall when it was built. even after the wear and tear of centuries, it remains over 450 feet in height. the pyramids are a majestic, remarkable feat of building. but who built them? some people like to suggest mystical origins: aliens, for example, or some superhuman race that existed before recorded history. but most archaeologists agree that the most amazing thing about the pyramids is that they were built by ordinary people. ordinary egyptians, working together, thousands of years ago, created beautiful tombs for their pharaohs. how do archaeologists know this? they have found evidence of the workers. during construction, the pyramids were surrounded by a workers’ camp, and evidence of these camps still exists today. the workers probably lived in tents, but the ruins of other buildings, such as a bakery, have been discovered. a workers’ cemetery reveals that the people who worked on the pyramids were primarily egyptians. they obviously had a doctor on site, because some of the human remains in the cemetery show signs of medical treatments for injuries like broken bones—exactly the type of injury you might expect an ancient construction worker to suffer. people claim it would be impossible for ancient workers to construct anything so elaborate, but researchers have proven that claim to be false as well. ancient drawings show some of the techniques that would have been used to move the huge stone blocks into place. modern researchers have used those techniques and determined that it would be possible to build the pyramids using human tools and human labor. it would take a long time, but history tells us that building the pyramids did take many years. perhaps the clearest evidence of all comes from inside the pyramids. the workers put up graffiti to “sign” their work. workers seem to have worked in teams, and they gave their teams nicknames. the team nicknames appear in various places within the pyramids. some of the graffiti appears in places that would be impossible to reach once the pyramid was constructed. putting all this evidence together, it is obvious to most researchers that the “magic” of the pyramids is really the magic of the human spirit. and isn’t that remarkable enough?

part a what is the central idea of this text?
a) another group of humans, not the egyptians, built the pyramids.
b) aliens built the pyramids.
c) scientists don’t know who built the pyramids.
d) egyptians built the pyramids.

part b how does the author of this text use details to develop the central idea described in part a?
a) the author cites three specific details—the camps, the techniques, and the graffiti—that prove egyptians built the pyramids.
b) the author includes an interview with an archaeologist who worked at the pyramids.
c) the author acknowledges that some people believe other groups built the pyramids.
d) the author asks questions about who built the pyramids because no one really knows.