Please submit your concern

Explanation:

As per the last sentence of the penultimate paragraph, the behaviour of elephants, especially orphans who have watched the death of their parents, is similar to the post-traumatic stress disorder exhibited by humans. So if you use similar treatment programmes for treating post-traumatic stress disorder that we use for humans, it might solve the problem of elephant aggression. Thus option 1 can be retained. As per the first sentence of the second paragraph, researchers have already studied the effect of high levels of testosterone and elephant aggression. Thus option 2 which states more funds to be made available for the study of the impact of testosterone and elephant aggression in incorrect and can be negated. The penultimate paragraph mentions how there is compelling evidence of the impact of isolating young elephants on early brain development, behaviour and aggression. Thus option 3 which states the same thing can also be negated. Since the passage talks only about elephants, option 4 which talks about researching the similarity of humans and other animals is beyond the scope of the passage and can be negated.
Hence, the correct answer is option 1.