Answer:
A snail eats a clam.
Explanation:
Interactions always occur between organisms in an ecosystem. An interaction between two organisms is called SYMBIOSIS. Symbiosis consists other types which includes PREDATION. Predation is a kind of symbiotic relationship between two organisms in which one kills and feeds on the other in order to obtain energy. The organism that kills is called the PREDATOR while the organism that is killed is called PREY.
In this example, a snail feeding on a clam best represents the example because the snail (PREDATOR) is obtaining energy by killing the clam (PREY). In other options, no organism is killed.
The independent variable is the new plant food