Which of the following is a recommended measure to prepare for a flood?

Elevating utilities such as the furnace and water heater is a crucial measure for flood preparedness. This practice minimizes the risk of these essential systems being damaged by floodwaters, which can lead to significant property damage and hazardous situations. By placing utilities on elevated platforms or in higher areas of a home, homeowners can protect their equipment from submersion in water, ensuring they remain functional during and after a flood event. This proactive approach serves to enhance the resilience of a property against flooding risks, making it a key recommendation for flood preparation.

The other options reflect practices that would increase vulnerability to flood damage. Building on low land without precautions would significantly heighten the risk of flooding impacts. Leaving basement walls unsealed would allow water to intrude more easily, and installing a basement without waterproofing would make it susceptible to flooding, all of which highlight the importance of taking preventative measures to mitigate flood risks.