Which part of Colby's narrative would be considered the falling action?

A. Colby realizes that Snickers is no longer in the
backyard.
B. Colby and wis dad fill the hole under the fence with
rocks so Snickers can't escape again.
C. Colby and four of his friends mount an expedition
through the neighborhood to find Snickers.
D. Colby soothes a terrified Snickers, who had wiggled
into a crawl space underneath the