"What does the fox say?"
Translation:Co říká liška?
You would use "co to říká" if you did not hear it properly or you were astonished by the content and want to repeat it.
I added it as a possibility here.
In the Czech-to-English exercise, "What does A fox say?" is also accepted. In this exercise, options both with and without ta are accepted. If you mean that there was no word bank tile for ta here, it is likely because ta is not included in the main translation, which is the one shown at the top of the page. In a "real world" scenario, whether the speaker means "a fox" or "the fox" could be derived from the context.
Not sure I understand your question, but... The hints are not 100 percent reliable for every sentence, because they often include options that are appropriate in a different context. This is one of those cases.
I have had exercises where ,in my answer I have omitted writing the the translation in czech and gotten it wrong. IN this case the in the fox is not in the answer. instead of ta liska ther is only liska and so I had wanted o know what teh czech answer be if the the translation was a part of the answer. Co rika ta liska??