Why is it not easy to replace a link in a food chain? The decomposers will not decompose another type of organisms.
There are not enough plants to replace the previous organisms.
There are not enough animals to replace the previous organism.
There may be limited type of natural predators organisms may have.

There are not enough animals to replace the previous organism.

Explanation:

There are not enough animals to replace the previous organism. The decomposers will not decompose another type of organisms. There are not enough plants to replace the previous organisms

the answer is either b or c

the answer is:  

line graphs show patterns in data with variables that change over time; whereas, circle graphs show data as parts out of a whole (such as out of 100%).