Predators are the keystone species because they limit the population of prey.
<h3><u>Explanation:</u></h3>
Predators are those species which hunt for other animals to consume them as food and live. Where prey are those animals who are being hunted and killed by predators.
Keystone species are those species whose absence or removal from a ecosystem will greatly reduce the diversity from the ecosystem to a huge extent.
Now, if a predator like lion is eliminated from the ecosystem, then the prey like deer, goats etc in the ecosystem will live and reproduce at a very high rate, which will greatly increase the population density of these species. So the food for them will be killed at a very high rate, decreasing the plant varieties and population. So the overall diversity in the ecosystem will be highly reduced.
So the predators like lions, tigers, etc are the keystone species of an ecosystem.
I would have to go with A
Quarantine is the modern strategy which could have assisted with the treatment of this communicable disease.
<h3>What is Quarantine?</h3>
This refers to the process in which animals, people etc are restricted from movement to other areas.
This strategy helps to tackle the spread of diseases to other parts of the world. This strategy wasn't employed which was why millions of birds were affected worldwide.
Read more about Quarantine here brainly.com/question/18945988
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