Answer:
a. Mass
Explanation:
The relation between the physical properties , luminosity and mass , is given by the formula -
L = M ^ 3.5
In which ,
L represents luminosity
and
M represents mass.
Hence , from the above formula ,
mass and luminosity are directly proportional to each other , i.e. ,
by decreasing the mass , the luminosity decreases
and by increasing the mass , the luminosity increases
higher luminosity means , higher temperature , and , in case the star has higher mass , its radius will also increase .