Answer:
d. Backlog review
Explanation:
Since in the question it is mentioned that the knowledge managemengt plays a vital role in the agile projects and at the end of every two to four weeks, there is a ceremony called a back log review in which it measures which function worked well and which can be improved
Here the backlog review means the list of the items which the team has to work. In this, the work should be done based on the existing work done and if there is any bug than it should be fixed. It could be applied while devloping a product all over the cycle
Therefore option d is correct