In Some Binary Star Systems, Such as Algol, the Less

In some binary star systems, such as Algol, the less massive star is an old red giant and the more massive star is on the main sequence, evidence that

A) the more massive star captured the other one into orbit sometime after the two stars had formed.
B) the more massive star formed later, from a disk of gas surrounding the less massive star.
C) mass transfer from one of the stars to the other has occurred.
D) stars evolve differently in binary star systems, with less massive stars evolving faster than more massive stars.