<span>B is quite close, but it defines the existing variation within the population, which is positive but only goes so far if there is not new material being introduced.
C and D decrease the genetic variation of a population
</span><span>So the right answer is A, because it actually results in new genes being created through mutation.</span><span> </span>
Crude oil is a very versatile fuel and is used to produce things like plastics, artificial food flavorings, heating oil, petrol, diesel, jet fuel, and propane.
