Aresearcher observes that, on average, the number of divorces in cities with major league baseball teams is larger than in cities without major league baseball teams. the most plausible explanation for this observed association is
a. the association is due to the presence of a confounding variable, namely the population of the city. (major league teams tend to be in large cities with more people, hence a greater number of divorces.)
b. the observed association is purely coincidental. it is implausible to believe the observed association could be anything other than accidental.
c. the presence of a major league baseball team causes the number of divorces to rise (perhaps husbands are spending too much time at the ballpark).
d. the high number of divorces is responsible for the presence of a major league baseball teams (more single men means potentially more fans at the ballpark, making it attractive for an owner to relocate to such cities).
e. none of the above.