|Question 10Verbal

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Elaine Ostrander led an international collaboration with Greger Larson and other researchers to study the evolutionary history of size differences in modern dogs, including very small breeds such as Pomeranians. The researchers determined that among dogs as a whole, there are many different variations of the gene that regulates the production of IGF-1 (insulin growth factor 1), a hormone that promotes growth. After reviewing the study, a student concludes that these variations must account for the observed variance in body size among dog breeds.
Which quotation from a scientist not involved in the study would most directly undermine the student's conclusion?
"The researchers' conclusions regarding the IGF-1 gene may not apply to other species given that dogs vary in size more than any other group of land mammals does."
A
"The gene that regulates IGF-1 production is one of multiple genes known to affect the size of dogs."
B
"In fact, only one-third of the most prevalent dog breeds carry the same variant of the gene regulating IGF-1 production."
C
"Variations of the IGF-1 gene result in substantial body size variance among dog breeds and may influence additional characteristics as well."
D