Imagine an Advanced Civilization Living on a Planet Orbiting at a Distance

Imagine an advanced civilization living on a planet orbiting at a distance of 10 AU (1.5 billion kilometers) from a close binary star system that consists of a 15 MSᵤn red giant star and a 10 MSᵤn black hole. The black hole is surrounded by an accretion disk. Sometime within the next million years or so, the civilization's planet is likely to be doomed because ________.

A) the red giant will probably supernova within the next million years
B) jets of material shot out of the accretion disk will shoot down their planet
C) the red giant star, which provides most of energy the civilization needs to exist, will soon be destroyed in the accretion disk
D) tidal forces from the black hole will rip the planet apart
E) the planet's orbit gradually will decay, as it is sucked in by the black hole