Noah and Luke lifted the canoe up from the riverbank, carried it across the yard, and placed it on the top rack.

When are the boys doing work on the canoe?

Work = Force x Distance

canoe_racks_61ef3eb435092.jpg

a
They do work only while carrying the canoe across the yard.
b
They do work from the moment they touch the canoe until it is on the rack.
c
They are not doing any work on the canoe at this time.
d
They do work as they pick up the canoe and as they lift it to the top rack.