The H G Line Has a Wavelength of 434

The H g line has a wavelength of 434.0 nm when observed in the laboratory. If the H g line appears in a stars spectrum at 434.5 nm, what is the radial velocity of the star?

A) 346 km/sec away from the observer.
B) 346 km/sec toward the observer.
C) 1.3*10⁸m/sec away from the observer.
D) 1.3*10⁸ m/sec toward the observer.
E) The radial velocity of the star can not be determined from this information.