Martin believes that the volatility of a stock is lower than indicated by the market prices of its stock options. He wants to speculate on that belief by buying or selling at-the-money options. Which of the following strategies would achieve Martin's goal? Select one or more alternatives: Sell a strangle: sell one call with K2 at E2 and sell one put with K1 at E1 (Note: K2>K1 ) Sell a straddle: sell one call with K at E1 and sell one put with K at E2 Sell a butterfly spread: buy two calls with K2, sell one call with K1, and sell one call with K3 ( Note : K1