Based on what the author of "what's black and white and red all over? " states about the unanswered riddle in lewis carroll's alice's adventures in wonderland, what can be inferred about carroll's readers?

a.
they each came up with their own answers to the hatter's riddle.

b.
they had heard the hatter's riddle many times before reading it in carroll's book.

c.
they knew that the hatter's riddle was one that did not have an answer.

d.
they very much wanted to know the answer to the hatter's riddle.