How does biodiversity brings stability to an ecosystem

It provides an ecosystem with a variety of diversity. Each living thing plays an important niche. With this niche, the ecosystem becomes fully functioning and allows for a specific number of species to sustain life in that ecosystem. However, if there is a disturbance within this ecosystem (an additional specie(s) is brought in), the ecosystem will endure a dramatic impact, typically leading to change. Nonetheless, Biodiversity is a beneficial asset to an ecosystem, without it the ecosystem will not be capable of providing life to most living things.  

Transpiration is the answer

Ithink that b is correct but just in case wait to see if someone else answers