Answer:
In the upper course of a river, one of the features commonly found is rapids. Rapids are areas of the river where the water flows swiftly over rocks or through a narrow channel, creating turbulence and rough water. Rapids are often associated with the upper course of a river where the gradient is steeper, and the flow is more turbulent. The other options (levee, headland, lagoon) are typically associated with coastal or lower-course features, rather than the upper course of a river.
Step-by-step explanation: