Answer:
If water and air deterioration have been described and studied for decades, soil contamination has become a priority only by late 1990s. Only in the last fifteen years, the importance of soil has been recognized as it represents the most important element for supporting life on Earth.2 Indeed, soil supports terrestrial ecosystems and human constructions, it regulates water cycle and carbon dynamics, decomposition takes place into the soil and the nutrients become available again. Soil provides food for human nutrition, and its quality represents a fundamental requirement for food safety, and therefore for animal and human health, even though not always this relationship is stressed enough
I think c but I'm not sure
Answer: Flinching at a butterfly because you were once attacked by butterflies.
Explanation: This is the only option that is a response to a normally neutral stimulus.
