Stellar formation

Two protostars have the same mass and radius. Protostar X accretes material at five times the rate of protostar Y. Which statement best compares their accretion luminosities?

Conceptual straight-line graph showing accretion luminosity increasing proportionally with mass-accretion rate.
For fixed protostellar mass and radius, accretion luminosity increases in direct proportion to accretion rate.