Correct Answer: option (D)Gist of the passage:1. Observation: people who do volunteer work tend to live longer than people who do not.
2. Finding:
(Doing good, for example, volunteer work) -> (release of endorphins in the body) -> (feeling of well being)
3. Conclusion:
There is a connection. Release of endorphins somehow leads to extension of people's lives. In other words -
(Doing good, for example, volunteer work) -> (release of endorphins in the body) -> (feeling of well being) -> (longer life of these people)
Question: Find the statement that will weaken the above logic (endorphins -> longevity).
Thought Process: 1. Any statement that provides another causality i.e. another reason for the long life other than endorphins is a good weakener.
(provides an alternate logic)2. Any statement that proves that (feeling of well being) does not lead to (longevity) is a good weakener i.e. (feeling of well being) -x> (longevity)
(breaks the existing logic)(A) People who do regular volunteer work are only somewhat more likely than others to characterize the work they do for as a ‘doing good.’Irrelevant. From the passage, we already know that (doing good) -> (release of endorphins). Whether the people feel they are doing good does not impact the chain of logic in the argument. For all we know, just the act of doing good subconsciously triggers endorphin release, irrespective of the conscious characterisation.
(B) Although extremely high levels of endorphins could be harmful to health, such levels are never reached as a result of the natural release of endorphins.Irrelevant to the argument. This only tells us that the levels of endorphins in this case are not harmful, because this is a natural release. This does not have any impact on our argument.
(C) There are many people who have done some volunteer work but who do not do such work regularly.Irrelevant. Frequency or regularity is not a factor considered in the argument. All we know is that if one does volunteer work, endorphins are released. The argument talks only about people who do volunteer, in general - no distinction made between those who volunteer regularly and those who volunteer occasionally. So, this has no bearing on the argument's logic.
(D) People tend not to become involved in regular volunteer work unless they are healthy and energetic to begin with.Correct! This is in sync with our type 1 of weakener (provides an alternate logic).
If people who tend to get involved in volunteer work are healthy and energetic to begin with, compared to people who do not volunteer, how can we be sure that the longevity observed is because of the volunteering work, and not because of the pre-existing better health of these people?
Hence, this is a correct weakener.
(E) Releases of endorphins are responsible for the sense of well-being experienced by many long-distance runners while running.Incorrect for multiple reasons.
What the option tells us:
In long distance runners, while they are running, (running) -> (release of endorphins) -> (sense of well being)
1. Can long distance runners (athletes - expected to be fit and healthy) be compared to the group of people in the argument (regular people who do volunteer work)?
2. Even if the group is relevant, the above option only states that (endorphins) -> (sense of well being). This is part of the author's logic. How can this be a weakener then?
So, this option is a definite no, as far as weakener goes.
Cheers!