The statement that must be true given a correlation coefficient of 0.72 between the number of professional sports teams in a city and the number of hospitals is:
As the number of sports teams increases, the number of hospitals tends to increase.
This statement reflects the positive correlation indicated by the coefficient of 0.72, which suggests that there is a strong association between the two variables, where higher numbers of sports teams are associated with higher numbers of hospitals.
The other statements make causal claims that cannot be concluded solely from the correlation. Correlation does not imply causation, so we cannot say that one causes the other based on the information provided.