Which of the following correctly describes the properties of unsaturated fats?

Unsaturated fats have specific characteristics that distinguish them from saturated fats. One key property is that unsaturated fats tend to have lower melting points. This is due to the presence of one or more double bonds in their fatty acid chains, which creates kinks or bends in the structure. These kinks prevent the molecules from packing closely together, resulting in a liquid state at room temperature.

In contrast, saturated fats have no double bonds and can pack tightly, leading to higher melting points and a solid state at room temperature. Thus, the property of being liquid at room temperature is a hallmark of unsaturated fats, making the choice indicating lower melting points and liquid state the accurate description of their properties.

Furthermore, while unsaturated fats tend to be less energy-dense than saturated fats, this is not the defining characteristic that distinguishes them based on their state at room temperature.