A pollutant is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource.
The answer is reproductive isolation. Reproductive isolation ensures members of different species do not produce offspring. In this case, geographical separation is ensuring that individuals from the two different populations are not able to mate with each other. Eventually, through different selective pressures, the two populations will diverge sufficiently in genotype to become distinctly different.
C is the proper answer. They have been reduced by using unleaded gasoline because lead can harm the air and water we breathe, so using less of it will help reduce the pollution being caused by it.
Hi the answer to your question is called the jugular notch and the cricoid cartilage that the thyroid gland is between.
Hope this helps.
