What makes a pesticide more likely to leach into groundwater?

A pesticide is more likely to leach into groundwater when it is very soluble in water and does not strongly adsorb to soil. High water solubility allows the pesticide to easily dissolve in water, increasing its mobility in the soil. When the pesticide does not strongly adsorb to soil particles, it means it can wash away with water during rainfall or irrigation events, thus moving through the soil and potentially reaching groundwater sources. This combination of characteristics significantly impacts the pesticide’s potential to contaminate groundwater, making option C the correct choice.