What can be done to enable the debug information for functions to be displayed when using ‘ksh - x’to debug a script?()
A.Run the script using 'ksh -fx'.
B.Run the script using 'ksh -a function -x'.
C.Edit the script and add 'set -x' at the beginning.
D.Edit the script and add 'set -x' at the beginning of each function.