[单选题]
The Feynman diagram shows twt;puy b lsuh+y2,5 6qio electrons approachingp(m7- cl 3m ii*ybywm+ each other, interacting, and then leaving each other. What particle is being exchanged during the interl (y-*7+iw3mimmbc ypaction?
A. pion
B. virtual photon
C. neutrino
D. $W$ particle