A steam of similar negatively charged particles enters an electrical field normal to the elctric lines of force with a velocity of `3xx10^(7)m//s` . The electric intensity is `100m` , the electrons beam is deflected by `2mm` . Then the specific charge value of in`C` `kg ^(-1)` is
A. `2xx10^(10)`
B. `2xx10^(7)`
C. `2xx10^(11)`
D. `2xx10^(4)`