Each of the following is a condition necessary for natural selection to occur except
a. more offspring are born than can survive b. population size is very largec. fitness varied among individualsd. there is heritable variation among members of the population

The four traits for natural selection according to Darwin are, variation, inheritance, high population growth rate, and differential survival and reproduction. Therefore the answer is A

what's the rest of the question

the statements that apply here about binary star system are

"have stars that might appear to wobble"

"often have one star that is brighter than other"

a binary star is a star system consisting of two stars revolving around their common barycenter. systems of two or more stars are called multiple star systems.