What scenario would make a partial bath unsafe?

Keeping the water temperature at 125°F makes a partial bath unsafe due to the risk of burns or scalds. At this temperature, the water is hotter than what is typically recommended for safe bathing, which is usually around 100°F to 110°F. The skin, especially in vulnerable populations like the elderly or those with sensitive skin, can sustain serious injuries from hot water. Maintaining a safe water temperature is crucial to prevent harm during bathing, making this choice the correct answer in the scenario described.

The other options describe practices that generally enhance safety and comfort during bathing, such as using a handheld shower, ensuring privacy, and having non-slip mats to prevent falls. These practices contribute positively to the bathing experience and do not inherently introduce risks like high water temperature does.