The Chinese words are illogically divided into panels (again). There is真 = really, and 好喝 = tasty, so please don't make panels '真好' and '喝'. It's like putting panels 'really ta-' and '-sty'. Makes no sense.
I also think 哪一種 is probably a good answer. It hasn't been taught yet, but that shouldn't be a reason not to accept it as an answer, especially since that isn't even the thing that is being taught in this lesson.
The 好喝 Word Bank tile is silent, they always stay silent for the entire lesson, I can't stand this lossage any more, so awful I'm dropping this Mandarin course. Please inform email@example.com if they ever fix it.