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.

weathering is the answer.

the correct answer is - d. china has a large and growing population.

the fact that china has a large (the biggest) population, and it is still growing, doesn't hinder the agriculture production in the country. in fact, it can for increased production in the agriculture, since there's more labor force, as well the sheer mass of people produces lots of scientists that come up with new inventions as to how to improve this sector. nice example is the inner mongolia region in china, in general dominated by the gobi desert, but few scientist came up with a nice idea as to how to make the region productive by using plants that are very resistant to droughts, so lots of people have been employed, and the region is becoming greener and greener each year, and the production of food in this region is also increasing.