Answer:
The sentence from this excerpt that is a fact is:
C. A German priest of the 1600s, Athanasius Kircher, wrote the first grammar and vocabulary of Coptic, the language of Christian Egypt.
Explanation:
"The Riddle of the Rosetta Stone" by James Cross Giblin is known for conveying the author's message by mixing facts and opinions. A fact is something that can be proven true and correct, something that has truly happened. Among the options given, that one that is a fact is letter C. It states something that happened and can be easily proven: someone wrote the first grammar and vocabulary of a certain language in a certain year.
If you look at the other sentences, you'll see they are permeated with opinions. When the author talks about letting [his] imagination run wild, making significant contributions, and producing nonsense, he is expressing his opinions. Other authors might very well regard those things differently.
