Which one of the following is a reason why astronomical distances are measured in light-years?
a
Distances among stellar bodies do not change.
b
Gravity of stellar bodies does not change.
c
Light always travels in straight line.
d
Speed of light is always same.
Physics & AstronomyAstronomical Distances & Light-yearastronomical distanceslight-yearspeed of lightstellar bodiesmeasurement units