Which of the following is true regarding extinction?
a. if the rate of speciation in a clade is equal to or less than the rate of extinction, the clade will survive. b. the rate of extinction is steady from clade to clade as are the number of species contained within a clade. c. single events or several causes working together to produce extinction in a short period is referred to as mass extinction. d. extinction that occurs in a relatively short period of time is referred to as background extinction.

C. Single events or several causes working together to produce extinction in a short period is referred to as mass extinction.

Example:
Destruction of forests, mountains, and bodies of water to satisfy human needs result to the imbalance of nature which also give rise to global warming.

Animals and plants have lost their habitats. They lost their means to live. They lost their food sources and they suffer and die because of humans irresponsible acts.

hope I helped!!

did you fail the test? xd

d. cellulose and starch