The answer possibly is C. ¯\_(ツ)_/¯
What is the connection between DDT and pyrethroids? They are both pesticides, but different ones. However, many mutations that protect the bugs from one of them also work on the other.
So, if they had been exposed, they'd be selected for resistence to these pesticides. But if they have not been exposed; they would be dying more often during the last decade.
It is known as ISCHEMIA.
Ischemia occur when there is an hindrance in the flow of blood to a particular organ in the body. Because it is the blood that carry oxygen round the body, such an organ will not get adequate supply of oxygen. Ischemia is usually caused by blockage or narrowing of the arteries.
I think it might be B but I am not sure