Answer: scientific theory is an explanation of observations or events that is based on knowledge gained from many observations or events.
"Mechanical" would be the kind of reproductive isolation among the choices given in the question that has been observed in these two species. The correct option among all the options that are given in the question is the first option or option "A". I hope that the answer has come to your help.
2 - Human refuse to stop polluting.
All other three are attempting to attack the problem of pollution.
<span><span><span>The experimental method is usually taken to be the most scientific of all methods, the 'method of choice'.</span><span> </span><span> </span><span>The main problem with all the non-experimental methods is lack of control over the situation.</span><span> </span><span>The experimental method is a means of trying to overcome this problem.</span><span> </span><span> </span><span>The experiment is sometimes described as the cornerstone of psychology</span>
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