Answer :
The third statement is hard to prove. Number one is not biased nor is two because it is probable though the word often is not very specific. Four is provable- there would be enough data to see who the bookmobile primarily serves. But there it is hard to prove that education is taken less seriously among the lower-income population. The third is the biased statement.
Though education is taken less seriously among lower-income populations, library budget cuts will still affect them.