I need opinion from Scrum SMEs and practitioners on the below question:
Product backlog refinement…
a) Must be completed before the sprint 1
b) Can be done during the sprint planning
c) Can be done during the sprint review
d) Must be done only during the sprint
e) Must be done only between the sprints
f) Must be done along with sprint backlog refinement
g) Can be done during sprint retrospective
h) Must be attended by PO and dev team