You are presented with the quiz "what can have a negative impact on humans if contained in food they eat?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "eating food that contains pesticides can have a negative impact on humans" and "herbicides are the leading type of pesticides, in terms of both user expenditure and volumes used". 

So, what's the best answer to the question?


 

        herbicide   