Answer: Answer in explanation
Explanation:
If you're talking about *stars* in general, as mass increases, so does the luminosity - it burns brighter and faster. A *star* will not increase it's mass generally, unless something falls into it; and generally - even if a *planet* falls into a star (take our sun, for example - you could plunge the Earth into the sun, and you've only increased the sun's mass by 1/1,300,000th... )
As radius increases, for example, when our sun slips into the Red Giant phase, it will become redder, but the surface will have increased 100,000 times - so, the amount of light it puts out now from a square meter, compared to how much it will put out when it's a red giant will be reduced 20 fold; however, there's so much ***more*** area, that the overall brightness of our sun will increase dramatically.