The sentence that plagiarizes from Isaacson is:
A
"When you first see the walls and pyramid at Saqqara, you may think they are a mirage. But they are not."
This sentence closely resembles the original text in its structure and wording, particularly in the phrasing about a mirage. The other options (B, C, and D) provide general information that is more widely known and do not closely follow the original wording or structure, thus they might not necessarily be considered plagiarism. However, they should still be cited if they refer to specific information from Isaacson's work.