The correct option is C 1.89×107m/s
Using, E=eV
E=1.6×10−16 J
where E is energy
e is electric charge of electron, 1.6×10−19 C
V is potential difference.
Now electron has kinetic energy only, this implies
E=12mv2
Mass of electron is 9.11×10−31 kg
Therefore, velocity v=1.8×107 m/s.