The answer is A. This ensures that the resource has enough time to regenerate so as to sustain consumption. An example is that of the carrying capacity of a habitat. If a herd of cows exceed the carrying capacity of the grazeland, the grass will be depleted and the area will be predisposed to desertification. The environment will not be able to sustain the cows anymore until the herd number reduce.
RNA contains cytosine and uracil as pyrimidine. DNA has cytosine and thymine.
I'm not 100 % sure but it may help you to have a look at this link -
http://www.answers.com/Q/What_is_the_formula_for_photosynthesis
Erosion? I took earth environmental 2 years ago so I might be wrong
The answer would be the Gastropoda
