Enforcement of local speed limits through police monitoring has proven unsuccessful in the town of Ardane. In many nearby towns, speed humps (raised areas of pavement placed across residential streets, about 300 feet apart) have reduced traffic speeds on residential streets by 20 to 25 percent. In order to reduce traffic speed and thereby enhance safety residential neighborhoods, Ardane' s transportation commission plans to install multiple speed humps in those neighborhoods. Which of the following, if true, identifies a potentially serious drawback to the plan for installing speed humps in Ardane? ['On residential streets without speed humps, many vehicles travel at speeds more than 25 percent above the posted speed limit.', 'Bicyclists generally prefer that speed humps be constructed so as to leave a space on the side of the road where bicycles can travel without going over the humps', 'Because of their high weight, emergency vehicles such as fire trucks and ambulances must slow almost to a stop at speed humps.', 'The residential speed limit in Ardane is higher than that of the nearby towns where speed humps were installed.']