We don’t know whether the whole-language method is ever successful in teaching how spoken language can be broken into component sounds. We know that many children who are taught using this method can learn how spoken language is broken into component sounds, but we don’t know whether they learned this from the whole-language method.

We know that learning how sounds are represented by means of letters is one necessary condition for reading an alphabetic language. But we don’t know that it’s sufficient. In fact, phonemic awareness is another requirement, so if someone doesn’t have phonemic awareness, they won’t be able to read, even if they understand how sounds are represented by letters.

Not supported, because someone who can’t read an alphabetic language might be lacking some other necessary condition that we don’t know about. It’s possible they have phonemic awareness and knowledge of how sounds are represented by letters, but still can’t read for some unknown other reason.

Must be true, becaue we know many children taught using the whole-language method can read alphabetic languages. So they must understand how sounds are represented by means of letters.

Not supported, because we don’t know that the whole-language method is how many children who learn to read alphabetic languages came to understand how sounds are represented by letters. It’s possible that they learned this through something else besides the whole-language method. In other words, just because they were taught using the whole-language method does not imply that this method is how they learned what’s necessary to read alphabetic languages.