Thanks for the feedback! I'd appreciate hearing how you (or the parent) think the wording could be improved. English isn't my native language, so suggestions are very helpful.
Maybe "Which question is solved by E?" or "How many questions are solved by E?" - another way would be "Which question has E as its correct answer? // Which question is answered by E?" or "How many questions are answered by E?"
I personally like the solved wording.
Also another vote for clearer colors about possibility state - for example, the cells are marked green if that specific answer is internally consistent, but it can still be an incorrect solution overall, which means you did not get the correct answer whatsoever.
I think people (myself included) have been trained to think green = good, meaning that answer is correct and shouldn't be moved, you found that one, now work on the others - so an intermediary color as mentioned, like yellow, meaning 'yep that's plausible but not necessarily right' would be a good fit there.
I would go with, "Which question has E as its answer?" or "the answer" instead of "an answer" would fix it for me.
Similarly, "How many questions have E for the answer?"
I think it also threw me because we have a trick question in English, "How many months have 28 days?"
All the months have 28 days, but people usually answer 1, so for those of us who are used to approaching questions, especially logic questions, as literally a as possible, all the questions have the answer E. It's just not the right answer. "How many questions have E as the answer?" would clear that up for me.