Which of the following properties of pesticides influences its movement to groundwater?

The property of solubility is crucial in determining how pesticides move to groundwater. Solubility refers to how well a substance can dissolve in water. When a pesticide is highly soluble, it can easily mix with water and be transported through soil layers, potentially reaching groundwater sources. This is particularly concerning because groundwater is a vital resource, and the contamination from soluble pesticides can have significant health and environmental impacts.

In contrast, volatility pertains to how readily a pesticide vaporizes, while color and odor are sensory properties that do not influence the chemical behavior of pesticides in terms of groundwater contamination. These attributes are less relevant when considering the potential for pesticides to leach into water supplies. Thus, solubility is the most direct factor affecting the likelihood of pesticide migration to groundwater.