Stock market investors are ready for the first U.S. Federal Reserve interest rate hike in nearly a decade next week, but they may not be fully prepared for all of the nuanced remarks likely to accompany that announcement. If the Fed lays out an aggressive schedule of future rate increases, stock markets could become very volatile and even plummet, say strategists who expect a market-calming central bank announcement detailing the patience of policymakers. Activity in the options market suggests stock traders are being cautious ahead of the Fed policy meeting on Dec.