Which "this"?

OK, so we blogged for a while, and we all quit. But I still want to practice. So here is a random question I haven't had time to research.

John 4:1-3 reads, "The Pharisees heard that Jesus was gaining and baptizing more disciples than John, although in fact it was not Jesus who baptized, but his disciples. When the Lord learned of this, he left Judea and went back once more to Galilee." (New International Version)

Which "this" did Jesus learn?

1. Jesus was becoming more popular than John.
2. The Pharisees heard Jesus was becoming more popular than John.
3. Jesus' disciples were baptizing people.

Depending on which "this" you take as the antecedant, you get a different picture of Jesus' possible motivation for going back to Galilee. Was it too early to be that popular in Judea? Was it to avoid confrontation with the Pharisees? Was it to keep His disciples from baptizing others?

The original Greek text may answer this, or may be as wide open as the English; I just haven't taken the time to look into it.