I believe the answer to this question is a food web.
Food Web definition: "<span>a series of organisms related by predator-prey and consumer-resource interactions; the entirety of interrelated food chains in an ecological community."
Source: </span>http://www.dictionary.com/browse/food-web
B. That is not related to the Structural adaptation. And are in you in K12?
Answer:
Structure that organizes motion of chromosomes. Cytoplasm. Material in cell; contains chemical wealth: sugars, amino acids, and proteins a cell uses to carry out everyday activites. Vacuole. Saclike structure (large in animal cell); stores water, salts, carbs, and proteins. Plays a role in disposing waste.
Explanation:
The correct answer would be A. The agent of metamorphism that would cause for the overall composition of a rock to change would be hydrothermal solutions. These solutions contain mineral substances that are dissolved in the hot water. When in contact with a rock, the minerals may change the composition of the rock.