Read the excerpt from The Riddle of the Rosetta Stone by James Cross Giblin.

He recognized immediately that the last two hieroglyphs were the same as two in Ramesses and read "mes." They were accompanied by the figure of a bird, an ibis. Champollion knew from reading ancient Greek books that the ibis was the symbol of Thoth, the Egyptian god of learning and magic. He decided the three hieroglyphs must represent the name of Thothmes, the "Child of Thoth," a pharaoh who ruled Egypt from 1501 to 1447 B. C.

Based on the excerpt, what detail did Champollion use to conclude that the hieroglyphics represent the pharaoh Thothmes?

A The title of Thoth as the god of learning and magic
B The dates that Thothmes ruled Egypt
C The symbolic meaning of the ibis
D The ancient Greek language