How do you set the Event Reason Derivation rule to ensure event reasons are NOT overwritten?

How do you set the Event Reason Derivation rule to ensure event reasons are NOT overwritten?
A . Set the IF statement to check if the event reason value is blank and set the THEN statement to NULL.
B . Set the IF statement to check if the event reason value is NOT NULL and set the THEN statement as blank.
C . Set the IF statement to Always True and set the THEN statement as blank.
D . Set the IF statement to check if the event reason value is NULL and set the THEN statement as blank.

View Answer

Answer: C