So ¿cómo está? is an incorrect answer for a child?
Don't remember ever hearing that one, only that it is okay to use the informal version with them.
Also you site is jumping past questions when I give the answer to a previous question, I know I should notice but your site shouldn't do that either.
It's happened a couple of time and I think I've done well on a test only to find out I didn't answer a couple of the questions.
Also there are drop downs that don't show some of the answer and lo and behold one of them is apparently the correct answer, which only confuses me because I end up picking the best sounding incorrect answer.