标签不会出现在d3力图上

I am a beginner at d3. One of the diagrams I find particularly helpful and fun is the d3 force diagram. I've been playing around with it, but for some reason I've had a lot of trouble with this particular data set. Specifically, I've been trying forever to get the labels to show up on my d3 force diagram, but it just won't work. Here is my code:I am a beginner at d3. One of the diagrams I fi