Eating unhygienic food always results in cases of stomach infection or

Question

Eating unhygienic food always results in cases of stomach infection or food poisoning. Dominic is currently suffering from food poisoning, so he must have eaten unhygienic food in the last few days.

Which of the following is an assumption on which the argument depends?

(A) Eating unhygienic food will most definitely lead to food poisoning.

(B) Dominic does not have a weak immune system that makes him prone to food poisoning.

(C) Dominic can identify the difference between hygienic and unhygienic food.

(D) Eating unhygienic food is the only way to get food poisoning.

(E) Unhygienic food contains harmful bacteria and other pathogens that lead to food poisoning.

wadhwakaran · Answer

Eating unhygienic food always results in cases of stomach infection or food poisoning. Dominic is currently suffering from food poisoning, so he must have eaten unhygienic food in the last few days.

A leads to B
Dominic has B, therefore he must have done A
A-- eating unhygienic food
B-- stomach infection or food poisoning

The above relation is only possible when we know that B only happens A has happened.

Therefore Option D.

Iotaa · Answer

The most apparent assumption for this argument is that eating Unhygienic food is the only reason for food poisoning.

(A) Eating unhygienic food will most definitely lead to food poisoning: It leaves other possible reasons for food poisoning.  Reject

(B) Dominic does not have a weak immune system that makes him prone to food poisoning: Irrelevant.  Reject

(C) Dominic can identify the difference between hygienic and unhygienic food: again, Irrelevant.  Reject

(D) Eating unhygienic food is the only way to get food poisoning:  Correct . Unhygienic food is the only way to get food poisoning; Dominic has food poisoning. Hence he must have unhygienic food.

(E) Unhygienic food contains harmful bacteria and other pathogens that lead to food poisoning: again, Irrelevant.  Reject

Answer is option  D

smbbourne007 · Answer

Analysis:  Eating unhygienic food -> stomach infection or food poisoning.  
Eating unhygienic food is  sufficient  to cause food poisoning, but we  don't know if it's necessary . 
If someone is suffering from food poisoning, we can't for sure tell that eating unhygienic food is the cause because it, eating unhygienic food, can be only one of the many ways to get food poisoning.

(A) Eating unhygienic food will most definitely lead to food poisoning. -  No, this is not an assumption . This is given in the argument (as a sufficient condition).

(B) Dominic does not have a weak immune system that makes him prone to food poisoning. - Doesn't matter. His  immune system will be of no help  because he is bound to get food poisoning if he eats unhygienic food.

(C) Dominic can identify the difference between hygienic and unhygienic food. - Doesn't matter.  He still can choose to eat it , causing food poisoning.

(D) Eating unhygienic food is the only way to get food poisoning. -> Yes, this has to be assumed to conclude because only when we have a single cause to an effect can we point to the cause given the effect has occurred.  No other causes can lead to the effect , so it must be due to eating unhygienic food.
Stomach infection or food poisoning -> Eating unhygienic food.

(E) Unhygienic food contains harmful bacteria and other pathogens that lead to food poisoning. -  Why unhygienic food leads to food poisoning is immaterial.

KK14 · Answer

Why is Option B incorrect? If I use a negation technique, because of bad immune system food poisoning can happen because of any other reason than unhygienic food.

ReedArnoldMPREP · Answer

Good question. Let's take a look at the argument:

Okay, so the conclusion is that Dominic ate unhygienic food. The premises are that he has food poisoning, and unhygienic food always causes food poisoning.

The question at hand is: Did dominic eat unhygienic food, or not? Which makes me wonder: is it possible Dominic could have gotten food poisoning from food that was NOT unhygienic?

.

So you looked at answer B:

(B) Dominic does not have a weak immune system that makes him prone to food poisoning.

This is tempting! Because at first glance it can look like "Oh, it wasn't that he ate unhygienic food, it's that he has a weak immune system!"

The problem here, though, is that a weak immune system could simply make Dominc more likely to get food poisoning (and not a stomach infection) from unhygienic food. So the negation doesn't ruin the argument. It just makes more likely one of the results of eating unhygienic food.

Answer D does what we need:

(D) Eating unhygienic food is the only way to get food poisoning.

If there are other ways of getting food poisoning, then I can't conclude he ate unhygienic food just because he has food poisoning.

KarishmaB · Answer

This question tests your understanding of conditional statements. It gives you a sufficient condition and concludes something you can conclude only from a necessary condition. Hence the assumption here is that the necessary condition also holds. Check out sufficient and necessary conditions here first: https://youtu.be/MmlwcTlHZz8 https://youtu.be/BW8Ijrhjjq8 Whenever one eats unhygienic food, result is stomach infection or food poisoning. Dominic is currently suffering from food poisoning Conclusion: He must have eaten unhygienic food in the last few days. Premise is that unhygienic food is sufficient for food poisoning. But the conclusion concludes that it is necessary. So the assumption is that unhygienic food is necessary for food poisoning. (D) Eating unhygienic food is the only way to get food poisoning. Hence option (D) works. (B) Dominic does not have a weak immune system that makes him prone to food poisoning. "prone to food poisoning" means "more likely" to get it. So if he eats even a tiny bit of unhygienic food, he could get food poisoning. A weak immune system is not given to cause food poisoning, just make the person more susceptible to it. This is a new variable which has no bearing on our argument. Answer (D)

KK14 · Answer

I am bit confused now whether this is causal statement or conditional statement

KK14 · Answer

Thanks for the explanation Reed Arnold. I got it. So B can't be an assumption, but it is certainly strengthening the argument.

KarishmaB · Answer

It needn't be one or the other. Both the following are equivalent:

Unhygienic food always results in stomach infection. - A causes B (But it may not be the only cause. Other things could cause B too)
Whenever one eats unhygienic food, result is stomach infection. - A is sufficient for B (But it is not necessary. Something else could lead to B too)

In my experience, thinking in terms of sufficient vs necessary resolves all problems in CR.

Deep1208 · Answer

Hi Team,
I was confused between A and D.

A)Eating unhygienic food will most definitely lead to food poisoning.

D)Eating unhygienic food is the only way to get food poisoning.

Can you elaborate on the term "most" and "only way".

This word alone blundered my assumption!

egmat · Answer

Deep1208  You need to understand the logical structure of the argument. The argument follows this pattern:
 
  Premise:  Unhygienic food  →  stomach infection OR food poisoning (always) 
  Observation:  Dominic has food poisoning  
  Conclusion:  Dominic ate unhygienic food

The flaw is  reverse reasoning . The argument concludes A from B, when we only know A leads to B.

Why Not Option A?

"Eating unhygienic food will most definitely lead to food poisoning."

This strengthens the forward direction: unhygienic food  →  food poisoning

But here's the problem:  We ALREADY know from the premise that unhygienic food "always" results in stomach infection or food poisoning. Option A doesn't add anything new, and "most definitely" actually  weakens  the certainty we already have.

More importantly, strengthening A  →  B doesn't help us conclude A from B.

Why Option D is Correct

"Eating unhygienic food is the only way to get food poisoning."

This establishes the reverse direction: food poisoning  →  unhygienic food

The word "only" is critical because: 
 
 It eliminates ALL alternative causes of food poisoning 
 Without this, Dominic could have gotten food poisoning from contaminated water, viral infection, medication side effects, etc. 
 The conclusion made in the question requires that no other cause exists

Apply the Negation Test:

Negate D: "Unhygienic food is NOT the only way to get food poisoning"

If this is true  →  Dominic could have gotten food poisoning from other sources  →  The conclusion completely falls apart

This confirms D is the necessary assumption.

Key Takeaway for Similar Questions

For Assumption questions with conditional logic:
 
 Map out the logical structure (if... then...) 
 Identify any reverse reasoning (concluding A from B when only A  →  B is given) 
 The correct assumption typically rules out alternative explanations 
 Use negation test to confirm

Hope this addresses your doubt! In case you still feel confused about anything, feel free to ask!

Eating unhygienic food always results in cases of stomach infection or

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Eating unhygienic food always results in cases of stomach infection or

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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