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 MSunred giant star and a 10 MSunblack 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 planet's orbit gradually will decay, as it is sucked in by the black hole.

b. the red giant star, which provides most of energy the civilization needs to exist, will soon be destroyed in the accretion disk.

c. tidal forces from the black hole will rip the planet apart.

d. the red giant will probably supernova within the next million years.

e. jets of material shot out of the accretion disk will shoot down their planet.

Option D: the red giant will probably supernova within the next million years.

Explanation: a black hole is termed as object that has great gravity that nothing e.g like light can escape it.

A red giant star are usually a star that is dying at the last stages of stellar evolution. A supernova does occurs in Galaxy like milky waves at least only one time in 50years and can be liken to star destruction or exploding nearby universe which is sometimes closer to earth. There are 2 different ways a star can supernova. They include a Type I supernova which involves a star gathering (accumulating) a neighbour's closeby matter till runaway nuclear reaction light up (ignites). The other Type II supernova are star which their nuclear fuel has run out and then

breaks down(collapse)by or due to its own gravity.

as university of miami psychologists debra lieberman and adam smith pointed out in a recent article in the journal current directions in psychological science, humans have social and psychological mechanisms to deter incest. with very few exceptions, marriages between brothers and sisters and between parents and their children are verboten in every human culture. the primary psychological anti-incest mechanism is the yuck response. even the idea of sex with their mom or dad, bro or sis is upsetting to most people. the psychologist jonathan haidt has found that nearly everyone is repelled by the prospect of brother-sister sex, even in hypothetical situations in which there is no chance of pregnancy).

the biological cost of incest

this raises an interesting question: just what’s so bad about incest? sure, having sex with your dad or your sister seems gross — but why? some anthropologists have argued that incest taboos are learned social conventions. this explanation, however, doesn’t make sense to me as it does not explain the widespread existence of anti-incest mechanisms in creatures ranging from cockroaches to chimpanzees. second, the incest taboo is about as close to a universal law as human moral rules get.

why should mechanisms to avoid incest be so widespread both in nature and across human societies? the answer is simple. the problem with having sex close with relatives is that there is an astonishingly high chance that your offspring will be born with a serious birth defect.