1. Which of the following may be swapped out when page faults occur: a)Kernel pages, but parts of the file system data structures, may not be swapped out. b)Processes and files' pages can all be swapped out. c)Pages containing files are usually not swapped out d)Only process pages may be swapped, but not library pages, as they may be called by other processes. e)Kernel pages could be swapped out and recalled later. f)Both process and library pages may be swapped to the swap space (backing store) to make room for other processes