[单选题]
In a nuclear reaction,u2du ;/be1ssxaa kmun5qhw *v .,p4g 9 what value is conserved in addition to electraldoush3xlb23db )7i2w pb , aa2 g.y-ic charge, energy, and momentum?uo-.a,sb gal b2i3y7 h)3wb22 aldxdp
A. atomic number
B. neutron number
C. nucleon number
D. none of the given answers
