The correct answer is: C. critical
A chute spillway is a type of spillway that is used to control the flow of water from a reservoir or dam. The flow of water over a chute spillway is usually critical, which means that the water is flowing at its maximum velocity. This type of flow is characterized by a sharp rise in the water level upstream of the spillway and a sudden drop in the water level downstream of the spillway.
The other options are incorrect because they do not describe the flow of water over a chute spillway accurately. Option A, uniform flow, is a type of flow in which the water is flowing at a constant velocity. Option B, subcritical flow, is a type of flow in which the water is flowing at a velocity that is less than the critical velocity. Option D, supercritical flow, is a type of flow in which the water is flowing at a velocity that is greater than the critical velocity.
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