Which scenario would most likely lead to pump cavitation?

Pump cavitation occurs when the pressure in a pump drops below the vapor pressure of the liquid, causing vapor bubbles to form and collapse, which can lead to damage and reduced efficiency.

In the case of a clogged skimmer basket, the obstruction can restrict the flow of water entering the pump. As the pump continues to try to draw water, the reduction in incoming flow can result in a drop in pressure which may lead to cavitation.

Similarly, a full hair/lint strainer can impede water flow into the pump, creating the conditions for cavitation. When the strainer is clogged, less water can reach the pump, leading to a pressure drop as the pump's suction tries to maintain its flow rate.

Both situations create a scenario where the pump may not get enough water, resulting in a risk of cavitation. It's important to ensure that both the skimmer basket and the hair/lint strainer are kept clear to maintain optimal water flow and pressure, thus preventing cavitation from occurring in the pump system.