In frame 8, an electron and neutrino emerge from the virtual
W- boson, and a u quark and d antiquark emerge from the virtual
W+ boson. In frame 9, the b quark and antiquark, electron,
neutrino, u quark and d antiquark all move away from one another.
What is wrong with this picture?
See the picture of e+ e- --> D+ D-. See all nine frames of this
picture together.