The answer is D.

Let's break the argument down logically: since dogs who get infected don't get severely sick, there is not much point - from the standpoint of public health - in inoculating them. this assumes that nothing else bad can happen to public health from dogs being sick. Since we know the disease affects dogs and humans, this means we need to assume that (D) Humans do not contract yersiniosis primarily from dogs that have yersiniosis.

As always, we can answer by elimination as well:
A Any person who has received the nasal-spray vaccine can safely receive the oral vaccine as well. irrelevnat - the conclusion is that dogs don't need to receive the oral vaccine, not humans
B Yersiniosis is one of the most common diseases that affect pet dogs. no - in fact, if this were not true it would strengthen the argument: if dogs don't get sick, no reason to inoculate them in the first place.
C The oral vaccine is less expensive than the nasal-spray vaccine. if anything, weakens the argument, in that it makes using the oral vaccine more attractive
D Humans do not contract yersiniosis primarily from dogs that have yersiniosis. Yes! if this were not the case, then not inoculation dogs would be a bug problem, because humans would be infected. We need this assumption to be true!
E The oral and nasal-spray vaccines are equally effective. not necessary to assume this - in fact, if the oral were less effective, it would strengthen the argument by making it less attractive
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Category: Assumption

Known Information:
Yersiniosis affects both dog and human
The vaccine available is in form of nasal spray.

Challenges:
Pet owners are unwilling to put their dogs through nasal spray vaccine.

Proposed Solution:
A new vaccine that can be administered orally for dogs.

Stated conclusion:
Yersiniosis is not severe in dogs , so inoculation of dogs using oral vaccine will not have significant public health benefit.

The stated conclusion state that even if the dogs are not inoculated , it wont affect general public health. Does that mean the infection in human and dogs are unrelated ? We need to find the answer choice that explains this.

A Any person who has received the nasal-spray vaccine can safely receive the oral vaccine as well - This does not talk about oral vaccine for dogs - Irrelevant.

B Yersiniosis is one of the most common diseases that affect pet dogs - Again this does not give information for our question. - Not the right choice.


C The oral vaccine is less expensive than the nasal-spray vaccine - Out of scope - we are not talking about price here.

D Humans do not contract yersiniosis primarily from dogs that have yersiniosis -If Humans do not contact disease from dogs , then not inoculating dogs will not have any impact on the public health benefit. This is the most logical choice we have seen till now.

E The oral and nasal-spray vaccines are equally effective - Again , this does not give information on how not inoculating dogs does not affect public health.


Ans: D
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