C.The unique role the species plays in an ecosystem .
The global air temperature increases after the volcanic eruptions. It has also been observed that this increase in air temperature causes lowered winter seasons, acid rain, haze, dust, and ash. This causes problems in breathing and other disorders in humans as well as animals.
For the answer to the question above, the answer is "Systemic Acquired Resistance''.
<span>it is a whole-plant resistance response and it occurs by following an earlier localized exposure to a pathogen. It is analogous to the innate immune system that can be found in the animals, and there is also an evidence that SAR in plants and innate immunity in the animals may be evolutionarily conserved.</span>