A Study Conducted at Cornell University Concluded That a Possible

Multiple Choice

A study conducted at Cornell University concluded that a possible link existed between TV viewing and autism in children.Researchers looked at two factors leading them to their conclusions.First, the researchers looked at autism rates in specific counties.Results indicated that as rainfall increased, so too did rates of autism, and conversely as rainfall decreased, so too did rates of autism.The researchers found this interesting because prior research reported that children watch more TV when it is raining.Second, the researchers looked at the percentage of households with cable TV subscriptions.Results indicated that as cable TV subscriptions increased, so too did rates of autism, and, conversely, as cable TV subscriptions decreased, so too did rates of autism.The researchers combined these two results to conclude there is a link between watching TV and autism.However in this study, population size was an) ____________ variable that needed to be considered.

A) extraneous
B) nuisance
C) attrition
D) history