Around a singly ionised sodium atom and in an orbit of radius `r` an electron moves with an angular velocity `omega`. The magnetic induction at the centre of the nucleus will be

Options

A. `(eomega)/r xx 10^-7`
B. `(eomega)/(2r) xx 10^-7`
C. `(eomega)/r^2 xx 10^-7`
D. `(2eomega)/r^2 xx 10^-7`.