2.1. In developed countries sub-replacement fertility is any rate below approximately 2.1 children born per woman, but the threshold can be as high as 3.4 in some developing countries because of higher mortality rates.
This is a very good question and the answer to it is option A. The common core set of genes is very similar between all organisms.
This is true because several facts, for example, all living beings on earth share the same gene code: DNA, all of them are based on DNA or RNA, which humans have it too. This was explained by Darwin's evolution theory, we are all descendants of just one single species, and because of that, all species have something in common between them.
That's why there's a possibility that a human gene can correct a defective gene in a yeast cell. Although this could really happen, we are not sure about it, it's a possibility, don't always be sure of something in biology, there's always more to understand and to learn.
The following are included in the freshwater biome : Rivers, Lakes , and Streams.
Oceans have salt/saline water so they are excluded.
