Which disturbance would result in primary succession? A-harvesting wheat by using a combine harvester at the end of the growing season

B-controlled burning to stimulate the growth of forest trees such as sequoia

C-the formation of Surtsey, a volcanic island off of the southern coast of Iceland

D-the effect of a large herd of elephants on the grasses and shrubs in an area

(99 points) be serious! how do farts work? how do you fart without it stinking? serious answers only

Which is the correct formula for photosynthesis

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.