Which statement is an example of a scientific theory?
a. all living organisms are composed of one or more cells, which came from pre-existing cells.
b. hummingbirds do not like the color white because they visit other colored flowers more often.
c. the amount that caffeine affects a person's heart rate differs based on the person's age.
d. the earth is the third planet from the sun and has one moon, which orbits the earth.

answer; i believe that the correct answer is(d) nondisjunction during meiosis;

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.