The vaccine for yersiniosis, a bacterial disease that affects both dogs and humans, has been available hitherto in the form of a nasal spray. Pet owners who are at risk of contracting yersiniosis get themselves inoculated, but are often unwilling to put their dogs through the trouble of getting a nasal spray. A new yersiniosis vaccine that can be administered orally is effective for dogs. However, since this disease is rarely severe in dogs, widespread inoculation of dogs using the oral yersiniosis vaccine will have no significant public health benefit.
Which of the following is an assumption on which the argument depends?
A Any person who has received the nasal-spray vaccine can safely receive the oral vaccine as well.
B Yersiniosis is one of the most common diseases that affect pet dogs.
C The oral vaccine is less expensive than the nasal-spray vaccine.
D Humans do not contract yersiniosis primarily from dogs that have yersiniosis.
E The oral and nasal-spray vaccines are equally effective.
Source:Crackverbal