[单选题]
An electron and a protonzyh y1dy j.cf,w q/-+y are separate3o8t e swpk7,nd by a distance of 1.0 m. What happens to the magnitude of the force on the first electrsp okn w,3t78eon if a second electron is placed next to the proton?
A. It doubles.
B. It does not change.
C. It is reduced to half.
D. It becomes zero.
