After manually editing; a regular expression (regex), which of the following statements is true?

After manually editing; a regular expression (regex), which of the following statements is true?
A . Changes made manually can be reverted in the Field Extractor (FX) U
C . It is no longer possible to edit the field extraction in the Field Extractor (FX) U
E . It is not possible to manually edit a regular expression (regex) that was created using the Field Extractor (FX) U
G . The Field Extractor (FX) UI keeps its own version of the field extraction in addition to the one that was manually edited.

Answer: B