ethan began making a model to show the processes which resulted in the formation of oceans. art shows three boxes connected with arrows. the label on the first box is 'sea floor spreading', second box is 'earth's plates meet',and the third box is labeled with a question mark. which of the following would be the next step in the process? (4 points) group of answer choices crust is broken down earth's crust moves earth's plates meet sea floor spreading