Critical Reasoning

A popular beach has long had a dolphin feeding program in which fish are given to dolphins several times a day; many dolphins get as much as half of their food each day there. Although dolphins that first benefit from the program as adults are healthy and long-lived, their offspring have a lower life expectancy than offspring of dolphins that feed exclusively in the wild.

Which of the following, if true, most helps to explain the lower life expectancy of offspring of dolphins feeding at the beach compared to other young dolphins?

(A) Sharks that prey on dolphins are less common in the open seas off the beach than in many other areas of the open seas where dolphins congregate.
(B) Many of the adult dolphins that feed at the beach are females that nurse their offspring there.
(C) The fish given to the dolphins at the beach are the same types of fish that dolphins typically catch in the wild.
(D) Many dolphins that feed at the beach with their offspring come to the beach only a few times a month.
(E) Adult dolphins that feed at the beach spend much less time teaching their offspring how to catch fish in the wild than do other adult dolphins.

OA: E

I am in confusion with this question. Would any one explain every option?
Would you please give me some techniques to tackle such type of questions?

Thanks.

can you please tell which option did u select. That you it would help boarders to explain better.

I selected E, but I was in confusion about the explanation of it. I was thinking that the adults in the beach are not teaching the child how to catch. As a result, the children can not catch food from outside. it has been mentioned in the passage that they are given 1/2 food. So, they are not becoming healthy.

On the other hand, I want to know whether there is any short tip to tackle "most helps to explain" type question.

Thanks.