Poor nutrition is at the root of the violent behavior of many young offenders. Researchers observed that in a certai...

tselimovic on July 21, 2015


The argument establishes that a diet high in nutrition is the cause for an improvement in behavior, the effect. As a general rule, is it acceptable to strengthen an argument the way (E) does, by demonstrating without the cause (a diet low in nutrients) there is no effect (no improvement in behavior). If the argument were to establish that sunshine leads to healthy plants, and if it is true that cloudy weather (no sunshine) does not lead to healthy plants, is the argument strengthened?

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Naz on July 28, 2015

Okay so what answer choice (E) is doing is trying to show that there was no variable "z" that caused the effect.

Remember, when we have a Cause & Effect Strengthen Questions, the way you can strengthen the cause and effect relationship (X causes Y) is to either show that (1) X does, in fact, cause Y, (2) show that Y is not causing X, or (3) show that third variable Z is not causing Y or X and Y.

This is what answer choice (E) is doing: it is confirming that it wasn't some other thing in the prison that caused the improvement in behavior, i.e. conditions were fixed in the prison. In this way, we are eliminating other factors that could have had an effect, which strengthens the argument that it was the improvement in food that caused the better behavior.

In your example about sunshine and plants, showing that cloudy weather does not lead to healthy plants helps us show that it wasn't some third factor, i.e. the soil was very nutritious, that brought about healthy plants.

Hope that clears things up! Please let us know if you have any other questions.

Kath on September 26, 2019

Could you explain answer choice D that why it is wrong? And, does it matter if the young offender "choose" the high nutritional food?

hfatima1 on September 10, 2020

can someone please explain why D is wrong?

hfatima1 on September 10, 2020

also, is E right because it provides a control group?

hoshman on June 3, 2021

^in a way yes, here we have violent inmates without the high-nutrition diet and they do not experience the improvements in behavior (no cause, no effect)

Victoria on June 6, 2021

Hi @hfatima1 and @hoshman,

Happy to help!

@hoshman is correct. Answer choice (E) strengthens the link between a poor diet and violent behaviour because Group 1 changed their diet and experienced an improvement in behaviour whereas Group 2 did not and their behaviour remained violent.

Answer choice (D) is incorrect because it does not strengthen the link between nutrition and behaviour. The study, combined with answer choice (E), shows us that a change in diet can result in an improvement in behaviour. However, with the offenders in answer choice (D), we do not know if they were ever violent. Maybe these offenders were naturally non-violent and their diet had nothing to do with their behaviour.

Hope this helps! Please let us know if you have any further questions.

Abigail-Okereke on January 31, 2022

Can someone please explain why C is wrong?

Ravi on February 4, 2022

C is wrong because eating a low-nutrient dense food doesn't meant that one has a low nutrient diet (part to whole flaw). Eating a piece of cake does not remove all of the other nutrients from a diet that is otherwise rich in them. That's why we can get rid of C.