If Genre Criticism Uncovers the Same Points Uncovered by Redaction

If genre criticism uncovers the same points uncovered by redaction criticism, then why use the redactional approach?

A) To compare the two texts in an attempt to find any differences in the points made
B) Editorial activity provides more empirical evidence for the aim of the text.
C) To show that the Gospels stand up to any method of scrutiny
D) As a means of interpretation