Answer:
Hello!
Your answer should be B. By the shift of its spectral lines.
Step-by-step explanation:
It is known that when studying space, to tell if a star is moving TOWARDS EARTH its measurements will move towards the RED side of the Spectrum...
MOVING AWAY will mean its measurements will move towards the BLUE end!
HOPE THIS HELPS!
itsMATT04
{i did a bit of research from revision guides so there may be some similar phrases! :)}