Read the sentences. Antarctica is a continent that is vastly underused. Filled with resources ranging from fish to minerals to oil, we are overlooking valuable opportunities for our nation's economy. What is the effect of the word vastly on the author's purpose? It emphasizes the author's argument that Antarctica is not being utilized nearly enough. It proves the author's argument that Antarctica is not being explored nearly enough. It demonstrates that Antarctica is filled with resources that are currently not being explored. It suggests that Antarctica holds the answers for solving the problems in our nation's economy.