Suppose two protostars form at the same time, one with a mass of 0.5MSun and the other with a mass of 15MSun. Which of the following statements are true?
A. The 15MSun protostar will be much more luminous than the 0.5MSun protostar.
B. The 15MSun star will end its main-sequence life before the 0.5MSun star even completes its protostar stage.
C. The 15MSun protostar will orbit the Milky Way Galaxy at much higher speed than the 0.5MSun protostar.
