Which markings are designed to provide organized use of parking areas?

The choice of "Parking bay" is correct because parking bays are specifically designed to organize vehicles in designated spaces within parking areas. These markings indicate where vehicles can park, delineating the individual spaces to maximize the use of the area and ensure smooth traffic flow. By using these markings, drivers can easily identify appropriate locations to park their vehicles, which helps in minimizing congestion and makes it safer for pedestrians as well.

The other choices refer to different types of designated areas. An unloading bay is meant for vehicles to temporarily stop and unload goods, while a delivery bay serves a similar purpose, focusing on loading and unloading for deliveries. Manila Bay, however, is not related to traffic or parking but is a geographical location. Thus, "Parking bay" is the most relevant option concerning organized vehicle storage.