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?
【选项】Motorists who are not familiar with the streets in Ardane's residential districts would be likely to encounter the speed humps unawares unless warned by s/s and painted indicators