Car sharing systems allow users to rent a car at one location within a city and return it to any other designated location in that city, which can cause serious problems of car availability and user demand within the city's system. Dr. Emily Johnson uses real-time data and predictive modeling to identify when a high number of users making one-way trips is likely to leave some locations within the system _____ cars and other areas with insufficient supply. Which choice completes the text with the most logical and precise word or phrase?