If You Discovered a Planet Orbiting Another Star, and the Planet

Multiple Choice

If you discovered a planet orbiting another star, and the planet had an orbital period of 2 years and a semimajor axis of 1 AU, what would be the mass of its parent star? You can assume the planet's mass is much less than the star's mass.

A) 0.25 M _$\odot$
B) 0.5 M _$\odot$
C) 1.0 M _$\odot$
D) 1.25 M _$\odot$
E) 2.0 M _$\odot$