varotkorn wrote:
Dear
AjiteshArunThank you for your kind response

)
I have one follow-up question regarding the highlighted portion above.
If the population of bats does
NOT increase with the introduction of MV lights, how does the absence of local concentrations of the flying insects on which bats feed reduce the population of bats?
Let's say:
Situation 1 : Before MV lights are installed, there are 100 bats (use A LOT OF energy) + 100 insects
Situation 2 : During MV lights are installed, according to you there are still 100 bats (use LESS energy, but the population is still the same) + 100 insects
Situation 3 : After MV lights are removed/replaced, the situation is the same as
Situation 1. So, there should be 100 bats (use A LOT OF energy)+ 100 insects
I do not get the logic if the population of the bats does NOT increase with MV lights, then how removing the MV lights (going back to Situation 1) reduces the bat population?
But if the population of the bats DOES increase with MV lights in Situation 2, then choice D makes sense.
Thank you in advnace !
Hi
varotkorn,
The correct option introduces
additional information that completely changes our view of how good the conclusion is. We cannot ignore it when we're looking at the question as a whole. Our discussion was mostly restricted to the combination of
the existing support and option B. Leave those for now though. Look at the structure of the argument:
SUPPORT 1
and SUPPORT 2
lead to CONCLUSION
because SUPPORT 3.
or
SUPPORT 1
+ SUPPORT 2
+ SUPPORT 3 → CONCLUSION
Support 1 and support 2 are already given to us. However, support 3 is something that we need to provide.
If we look at support 1 and support 2
alone, then,
in the absence of any further information, we have no reason to think that the population will decrease the way the conclusion asserts it will. Because support 1 and support 2 do not affect the population (but the conclusion is about a decrease in the population), the correct option (the additional information) must have some impact on the population. A quick example:
Support 1: When a company operates a canteen in its campus, employees who cannot bring meals from home have their meals almost exclusively in the company canteen.
Support 2: Company X's canteen is about to close.
Conclusion: This change is going to lead to a drop in the number of employees at company X who cannot bring meals from home because
support 3.
Candidates for support 3:
B Employees who cannot bring meals from home are unlikely to eat home-cooked meals.
D In the absence of a canteen, employees who cannot bring meals from home spend so much time and energy finding food that they can't get any work done.
With option B, we're really not looking at a mass exodus of employees. Sure, they can't bring food from home, but they could always go back to doing whatever they were doing when there was no canteen (they could go outside the campus, or they could get something delivered).
D, on the other hand, finally gives us a reason to believe that employees will leave (or be forced to leave) as a result of this change.
Please excuse the choice of example. I've been reading about how tech companies invest in canteens to get more work out of their employees.

I am still a little bit confused here. Sorry for the inconvenience caused to you
before the mercury-vapor streetlights were installed, then the population of the bat would not change right?
insects. So, there should be no problem here.