#6 - A study was designed to establish what effect, if any

[Dave Killoran]

Complete Question Explanation

Weaken-CE. The correct answer choice is (B)

The stimulus describes a study done to establish the possible long-term effects of offshore oil rigs on the sea bottom life. Since there were no differences near the rigs vs sites several miles away, the researchers concluded that oil rigs do not harm the sea bottom animals:

• Cause Effect
  
  Oil Rigs Harm Sea Bottom Animals

This causal conclusion is unusual in that it presents a negative relationship, where the cause does not create a certain effect. This is still a flawed conclusion, but when a causal relationship is denied then to weaken the argument you need to find an answer that supports a connection between the cause and effect, and shows the rigs do cause harm.


Answer choice (A): This answer gives us no information about whether any damage has actually occurred, and thus it is incorrect.

Answer choice (B) is the correct answer choice. This answer shows that the control sites a few miles away might not be affected by the oik rigs, but that other areas, further away, could well be showing damage. Since this answer would show damage and reinforce the idea that oil rigs could have caused it, it is correct.

Answer choice (C): The stimulus stated that there was no difference between the sites, and thus it does not apply to the control sites.

Answer choice (D): This answer gives us no information about whether any damage has actually occurred, and thus it is incorrect.

Answer choice (E): This answer gives us no information about whether any damage has actually occurred, and thus it is incorrect.

Note how many of the incorrect answers simply supply responses that discuss elements of the fish population or sea floor without actually giving any indication that something negative has occurred. These answer can all be eliminated relatively quickly.

[sherrilynm]

I'm not sure why A is incorrect. I understand why B would be correct, but why is A wrong? I picked A because the study claims that since there are no differences between the two sites, no damage has been done.

However, doesn't A hurt this argument? I took it to mean that the researchers are looking in the wrong place. Sure, the two sites might not show damage, but what if the evidence of damage is actually in the decrease of commercial fish catches, NOT in changes to the two sites?

[Adam Tyson]

You've hit on exactly what is wrong with answer A, sherrilyn - it's the "what if" portion of your post! What if it does impact commercial fishing? Okay, that's bad. What if it doesn't? Okay, that's not bad. Which is it? We don't know! Answer A tells us one way that we might be able to determine that the sea bottom has been adversely impacted, but it doesn't tell us anything about the actual results.

An additional problem with answer A is that it fails to connect us to the oil rigs. Let's say we do some research and we find that commercial catches are down. Does that mean the oil rigs are to blame? Did we look downstream from the oil rigs? Do we know where the fish we caught had been feeding? Oil rigs might be the cause, but so might sunspot activity or weapons testing by the Navy or any number of other things.

Answer B is very definitely telling us that we looked in the wrong place. Not just that we might have, but that we did, and that is a much bigger weakness.

I hope that clears it up!

[sherrilynm]

That makes a lot of sense, thanks Adam!

[lsat_novice]

I'm struggling to understand why B is correct.
The stimulus says that the tested control sites are "several miles" from the rigs. And B says that oil from the rigs is often carried "considerable distances before it settles on the ocean floor." It doesn't seem like B contradicts the stimulus in any way.

[Adam Tyson]

That depends on whether "several miles" is a "considerable distance", lsat_novice! It's relative, perhaps, but a "considerable distance" could be much, much further away than just several miles. If that's the case, then the discharges could be having an impact somewhere far away, even while the control sites show no signs of any impact.

While this answer leaves some wiggle room in that interpretation, don't forget that the instructions tell us to pick the best answer, rather than a perfect answer or even a good one! There's no other answer choice here that does anything to undermine the argument, while this one should at least make you wonder whether perhaps the conclusion might be incorrect. That's enough to weaken the argument! Not destroy, but weaken.

Was there another answer that you felt did more damage to the argument? If so, let's talk about that and see if we can shed more light on it for you.

[apex4224]

Could you help me understand why answer choice C is wrong?

[KelseyWoods]

Hi apex4224!

The conclusion in the stimulus that we are trying to weaken is "oil rigs had no adverse effect on sea-bottom animals." Answer choice (C) is about the negative effects of "sewage and industrial effluent," not oil rigs. Furthermore, we know from the stimulus that there were no significant differences between sea-bottom communities near oil rigs and those located several miles away. So answer choice (C) does not help us show that oil rigs might actually have an adverse effect on sea bottom animals. Even if it is true that sewage and industrial effluent reduces species diversity and density of animal life, does that necessarily mean that oil rigs specifically are having this adverse effect? Nope!

Hope this helps!

Best,
Kelsey

[ashpine17]

I don't understand the explanation for why C is incorrect. When the stimulus states that there were no significant differences, how am I to interpret that? In everyday language, no significant difference means no big difference but I also know in certain fields like the sciences insignificance can be interpreted as being of negligible difference, like statistically insignificant. How am I supposed to interpret that term here?

[Rachael Wilkenfeld]

Hi ashpine,

Remember that the LSAT does not require any subject specific knowledge. So it wouldn't be using the term significant in a technical sense here, but an everyday sort of sense. So in this case, where the author says there's no adverse effect, we are looking for any effect that would be negative and meaningful. Answer choice (C) is wrong here because it doesn't address the key issue, the difference between the areas close to the rig and areas further away. Per the stimulus, either the complete destruction of the sea life or a decrease in density and diversity of sea life would have been noted as a significant impact.

Hope that helps!