The correct SEDCMD setting to mask the credit card numbers, ensuring that the masked version replaces each digit with an "x" character, is Option A.

The SEDCMD syntax works as follows:

s/ starts the substitute command.

(?cc_num=\d{7})\d{9}/ matches the specific pattern of the credit card number in the logs.

\1xxxxxxxxx replaces the matched portion with the first captured group (the first 7 digits of the cc_num), followed by 9 "x" characters to mask the remaining digits.

/g ensures that the substitution is applied globally, throughout the string.

Thus, Option A correctly implements this requirement.

Splunk Documentation Reference: SEDCMD for Masking Data