A diver's body heat is lost through conduction (primarily) at a rate of approximately how many times more rapidly than in air?

The correct answer is that a diver's body heat is lost through conduction in water approximately 25 times more rapidly than in air. This significant difference in heat loss is primarily due to the thermal conductivity of water compared to air. Water has a much higher density and a greater capacity to absorb heat, allowing it to draw heat away from the body much more efficiently.

In practical terms, when a diver is submerged, the heat lost through conduction can lead to hypothermia if not addressed through proper thermal protection, such as wetsuits or drysuits. Understanding this concept is crucial for divers as it emphasizes the importance of managing body temperature in aquatic environments. The other options reflect lower estimates of heat loss, which do not accurately convey the pronounced effect of water's thermal properties on the body, leading to a misunderstanding of how quickly a diver could become cold in the water.