The answer is B An observation about the number or amount of something
I think the correct answer from the choices listed above is option A. The process that is being described above is called succession. Ecological succession is the process of change in species structure in a community as time goes by. Hope this answers the question.
Sea otters are a keystone species. They play an important role in the health and stability of near shore marine ecosystems. They eat sea urchins and other invertebrates that eat vast quantities of giant kelp. ... Providing habitat is one of many services kelp offers to the marine ecosystem.
Well one is independent segregation of maternal and paternal chromosomes and another is crossing over