"Surprising" Phenomenon
Why do runners who train by running for shorter periods of time every day perform better than those who train by running longer periods of time?
Objective
The correct answer will present an unsatisfactory hypothesis, one that fails to explain why athletes who train on shorter times perform better in marathons. Every wrong answer, meanwhile, will state a difference between runners who train by running 90 minutes a day and those who train by running 120 minutes a day that explains this discrepancy.
A
The longer the period of time that one runs daily, the greater the chances of suffering adverse health effects due to air pollution.
This would explain why runners who train on shorter times achieve better results. Those who run for shorter periods are less likely to suffer consequences from air pollution that would hinder their training or slow them down during a race.
B
The longer the period of time that one runs daily, the easier it is to adjust to different race lengths.
This would explain the opposite discrepancy. If runners who train on longer time periods can adjust more easily, then if anything they should perform better than runners who train on shorter time periods.
C
The longer the run, the more frequent is the occurrence of joint injuries that significantly interfere with overall training.
This is a reason runners who train on shorter periods achieve better results. Less time spent training means a lower risk of injury, which means a higher chance of training consistently.
D
Runners who train over 90 minutes per day grow bored with running and become less motivated.
This would explain why runners who train on shorter time periods achieve better results. Those who run 90 minutes a day are less likely to lose motivation, and thus more likely to maintain their training and perform to their abilities.
E
Runners who train over 90 minutes per day deplete certain biochemical energy reserves, leaving them less energy for marathons.
This would explain why runners who train for 90 minutes a day achieve better results. They do not deplete their energy reserves before race day, while those who train on longer time periods use some of those reserves in training.
Summary
The stimulus says that eating Lathyrus sativus (L.S.) can cause domestic animals to develop a severe disorder called lathyrism. However, researchers have failed to use rats to study lathyrism. This is because rats that ate L.S. didn’t develop lathyrism symptoms.
Strongly Supported Conclusions
These conclusions are strongly supported:
Not all animals that eat L.S. will develop lathyrism.
Rats are less vulnerable to lathyrism than at least some other animals.
Not all animals that eat L.S. will develop lathyrism.
Rats are less vulnerable to lathyrism than at least some other animals.
A
The physiology of rats is radically different from that of domestic animals.
This is not supported. The stimulus doesn’t offer any general facts about the physiology of rats versus domestic animals. We don’t even know why rats don’t develop lathyrism, let alone if it’s due to a “radical” difference in physiology.
B
The rats did not consume as much Lathyrus sativus as did the domestic animals that contracted lathyrism.
This is not supported. Nothing in the facts suggests how much L.S. is needed to cause lathyrism in domestic animals, how much the affected domestic animals actually eat, nor how much was given to the rats.
C
Not all animal species are equally susceptible to lathyrism.
This is strongly supported. The stimulus says that rats don’t develop lathyrism from eating L.S., even though lathyrism is widespread in some domestic animal species. This lets us infer that different species of animals have different susceptibility to lathyrism.
D
Most of the animals that can contract lathyrism are domestic.
This is not supported. The stimulus mentions that lathyrism occurs in some domestic animals, but doesn’t indicate whether or not it can occur in non-domestic animals. Because we don’t know anything about non-domestic animals, we can’t compare.
E
Laboratory conditions are not conducive to the development of lathyrism.
This is not supported. The facts strongly imply that the problem with these lathyrism studies is that rats don’t develop lathyrism; nothing suggests that the laboratory conditions themselves are to blame. We don’t even know for sure if the studies happen in a laboratory!