C. To show that the General had a difficult time saying something.
Explanation:
In this excerpt, Twain uses the expression "to find his voice." This is an idiom that means that the general could not speak. This is Twain's way to say that the General had a difficult time saying something. This is likely a consequence of the fact that the General is in shock due to the actions of the man.
The narrator tells how "Earth: The Planet" has undergone several name changes. What point might the author be making? The author uses the name changes to suggest that the whole planet has been just a brand for centuries
