The answer would be A. thick filaments!
a)121 million gigatons or 121 million billion metric tons" of carbon).
B)The ocean, with around 38,000 gigatons
c)60 gigatons of carbon
The answer is D. The natural selection is a theory which illustrates the gradual process of evolution in the population due to the change of environment. The key point is the mutation (variation) exists in the population before the environment changing. For C, if the environment does not change, though the adaptation is useful to environment, it will not be selected. Because the organisms without the adaptation will not die.
The answer to this question is B. Asp
