How can obtaining oil harm the environment ?

answer: environmental impact of oil. oil pollution can have a devastating effect on the water environment, it spreads over the surface in a thin layer that stops oxygen getting to the plants and animals that live in the water. oil pollution: harms animals and insects.

explanation:

answer; i believe the answer is hydraulic action;

a tetrad is the foursome during meiosis made by two homologous chromosomes that have each already replicated into a pair of sister chromatids.