The difference between protons and neutrons are that one has a positive charge and one has a neutral charge. The similarities between the two is that they both make up an atom. The Electrons in an atom are in orbit of the cell inside the Electron cloud and is kept in the cloud by electromagnetic force.
I say it is all of the above.
Ecosystems experience change through human activity and natural events. This is because human activity can impact changes in nature, like climate for example. As a result, ecosystems change in response to the change in nature or natural events, which was caused by human activities. They are interrelated so to speak.
It must be C, at the Pacific Ocean