Although most biologists believe that many species are becoming extinct each year because of the activities of humans, relatively few species actually appear on compiled lists of extinct species. what is one reason why so few species are listed as extinct

Your answer would be "Many species are unknown to science and go extinct before they've been described."

Definition:

Extinct:

A specie that no longer exist.

Explanation:

The reason why "Many species are unknown to science and go extinct before they've been described" would be the correct answer because most of the species that are logged as "extinct" were barely discovered. To be exact, in order for a scientist to call a specie "extinct," they would have to discover it first. Through what scientist called evolution, there were many species that were living on earth that we don't know of. Since we don't know all of the species that lived on earth, we can't determine how many species are actually extinct. Scientists have discovered things like fossils for dinosaurs, fish, and etc that helped determine if they were extinct or not, in which they were. They marked the species as extinct because they discovered that there were species like the ones they discovered. If we keep discovering more species that we don't know of, then we can call them "extinct" since we don't see them around no more.

the correct answer, according to e2020, is the second choice there is an occluded front in region a and a cold front in region b.

helicase, i think thats it