Question

An observer that stands still as the electron moves by him, will observe ___.

Answer 1

When charge is placed near to us whether it is stationary or if it is in motion then we can say it will produce electric field.

Now when charge is in motion then it will also produce electric current

So due to a moving charge there is some magnetic field also near it

it is given as

$B = \frac{\mu_0 qv}{4\pi r^2}$

So here we can say that nearby a moving charge we must have experience the effect of electric field as well as magnetic field

so the correct answer must be

B) An electric & magnetic field