There exists much variation of traits within a species population. There are also limited resources that all members of the population have to compete for. Those with traits that make them better adapted to their environment will result in their survival, their ability to reproduce, and to pass on their traits to the next generation. This is an example of

The correct answer is "natural selection".

Explanation:

Natural selection is a process described by Charles Darwin, where individuals with advantageous traits are selected by nature under the premise of "survival of the fittest". The creation of these advantageous traits are the result of one or more spontaneous mutations that bring an adaptation that last in a species because it represent a better chance of survival for them.

sheep is a herbivore animal whereas grasshopper belongs to the class chordates but both of them feed on greens.  

if grasshopper and sheep feeding on a pasture land, i do not think both of them will have any impact on each other. however, the number of the species can make difference. since sheep feed on greens, there is a possibility there left no pasture land for the grasshoppers or they may get extinct.

i was thinking 4.0 v hope this