Select all items below that are examples of physical processes.

a. erosion

b. Great Barrier Reef

c. irrigation

d. mountain roads

e. plate tectonics

f. weathering

I believe the answers are erosion, irrigation, plate tectonics, and weathering. They are all natural, physical processes. The others are not processes. The Great Barrier Reef is perhaps a result of a physical process but is not a process itself. The same goes for mountain roads.