Which of the following statements best describes Material Safety Data Sheets (MSDSs)? O a. MSDSs are a primary method of informing employees about health risks and handling instructions associated with chemicals and potentially hazardous substances. O b. MSDSs replace the Hazard Communication Standard under federal employee safety law O c. MSDSs are safety data collection instruments that were ruled illegal by the U.S. Supreme Court O d. MSDSs are sheets used by transportation workers such as truck drivers to reduce absenteeism