Why are milky layers of hailstones less durable than clear layers?

The correct choice highlights that milky layers of hailstones contain more air trapped within them, which leads to a lower density compared to clear layers. This increased air content affects the structural integrity of the hailstone. The presence of air pockets reduces the overall mass and strength of the hailstone, making the milky layers more susceptible to breaking apart upon impact or during turbulent atmospheric conditions. In contrast, clear layers are more compact and dense, resulting from the freezing of water droplets that are typically larger and have a higher water content, giving them greater durability and resistance to shattering. Understanding the physical properties of hailstone formation is crucial when analyzing their behavior during severe weather events.