Help not sure what it means

Question 1 of 102 pointswhich best describes adaptive radiation? oa. geographical isolation caused by an adaptationob. biodiversity resulting from few ancestorsoc. a decrease in the rate of speciationd. adaptations that organisms teach each other

Describe the response the kidneys have to dehydration and excessive water intake. what happens to the concentration of urine in each case ?

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above