In comparison they both show feeding relationship in an ecosystem.
In contrast, a food chain is a simple linear feeding relationship while a food web is a complex feeding relationship.
2) The arrows is to show the direction of the feeding relationship
Because the energy is going to decrease to also nothing and the animals at the top have to hunt more than those closer to the bottom of the food web
The most appropriate answer is A !!
They replicate fast - producing more of the useful proteins such as the hormone insulin.