A nurse is reinforcing teaching about home safety with the guardians of a toddler. Which of the following statements by a guardian indicates an understanding of the teaching?

A. "The water heater should be set to 120 degrees Fahrenheit or less.": Setting the water heater to 120°F (49°C) or lower helps prevent scald injuries, which are a major risk for toddlers due to their sensitive skin. B. "I can leave my child alone in the bathtub for up to 15 minutes after they learn to swim.": Toddlers should never be left alone in the bathtub, regardless of their swimming ability. Drowning can occur in seconds and in very small amounts of water. C. "Open windows are safe as long as the screens fit snugly.": Window screens are not designed to prevent falls. Toddlers should be kept away from open windows, and window guards should be used for safety. D. "I will tell my toddler to never touch a firearm.": Verbal instruction alone is not sufficient. Firearms must be securely locked and stored out of reach, as toddlers may not understand or follow verbal warnings reliably.