The correct order of the processes of soil erosion from the options provided is:

1. Splash erosion

2. Sheet erosion

3. Rill erosion

4. Gully erosion

This order represents the progression of erosion processes as follows:

First, splash erosion occurs when raindrops hit the soil surface, dislodging and splashing small particles.

Next, sheet erosion occurs when water flows over the entire surface, carrying away a thin layer of soil evenly.

Then, as water concentrates into small channels, rill erosion occurs, forming small channels or rivulets on the soil surface.

Lastly, if rill erosion continues and intensifies, it can lead to gully erosion, which involves the formation of deep and wide channels or gullies in the landscape.

So, the correct order is: Splash erosion, Sheet erosion, Rill erosion, Gully erosion.