Final answer:
The correct order is c) Pioneer species, Intermediate species, Climax community.
Step-by-step explanation:
The correct order of labels in the flowchart to complete the model of secondary succession as observed in a deciduous forest of eastern North America is c) Pioneer species, Intermediate species, Climax community.
Secondary succession begins with the establishment of pioneer species, which are the first plants to grow back after a disturbance. These pioneer species are usually annual plants, followed by quickly growing and spreading grasses and other plants. Over time, intermediate species like shrubs, pines, and young oak and hickory trees emerge. Finally, after many years, the forest reaches its equilibrium point and resembles the community before the disturbance. This equilibrium state is called the climax community.