Answer:
B
Step-by-step explanation:
Not all disturbances to an ecosystem are harmful. Most natural disturbances, such as fires, floods, and volcanoes are actually useful. They mitigate the dominance of a few species in an ecosystem and therefore increase biodiversity. For example, fire destroys the canopy of a forest and gives a chance to shorter shadow-intolerant trees at the forest floor to flourish. These plant also supports a wide range of higher organisms hence increasing the biodiversity of a forest. Volcano also revitalizes the ecosystem by bringing in new minerals and making the ground fertile for secondary succession.