The organizational pattern that would probably be most effective for arranging the main points of a speech with the specific purpose "To inform my audience of the causes and effects of the erosion of America's seacoasts" is this:
The causal organization pattern is a way of arranging text by showing the causes and effects of an issue at hand. When a text is arranged in this manner, the reader will be able to easily point out what the problems are.
They will also be told the solutions to these problems. There are other organizational patterns that include chronological, descriptive, analytical, etc.
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