The right answer is the D: Are fruits and vegetables that are grown on farms that use pesticides dangerous for human consumption? This question is asking specifically if fruits and vegetables that have been grown with pesticides, or in farms that use them, are harmful for human consumption. Since the research is focused on identifying the harmful effects of food pesticides, it is not that key to know which pesticides are most commonly used (option A), where are most pesticides manufactured (option B) or what is the cost of protecting crops for human consumption that are grown using pesticides (option C).