The answer says “any character” not “any characters”, so it is still correct.

ITT: People misinterpreting the idea as “facts that your school taught wrong”, when it’s really saying, “things that have changed since you went to school” (either through a change in definition or by new research).

E.g. If you went to school before the early 2000’s, you were taught that Pluto is a planet, while that is no longer true since it was recategorized in 2006.