TITLE: Which letter is not homeomorphic to the letter $C$?
QUESTION [5 upvotes]: Which letter is not homeomorphic to the letter $C$?
I think letter $O$ and $o$ are not homeomorphic to the letter $C$. Is that correct?
Is there any other letter?

REPLY [8 votes]: From the wikipage on topology, here are the equivalence classes (under homeomorphism) of letters of the English alphabet. Any letter not in the same bracketed set as 'C' is not homeomorphic to it.