The correct answer is B.
IPM (Integrated Pest Management) is a mechanism which aims to practice the economically viable control of pests. It consists on implementing the adequate measures to prevent the proliferation of pest populations, but keeping pesticides at the lowest level, provided that they do not constitute a threat to human health, or a minium one, and only if their application is justified by economic interests.
IPM was implemented in Indonesia in 1986, by prohibiting the use of 57 pesticides in rice crops and cancelling the subsidies for pesticides (about US$120 million a year). Also, the intention was to limit the resurgence of BPH (the main pest in rice crops), as it was becoming resistent after an excessive use of pesticides in Indonesia. The yields were intensively decreasing due to the spread of that pest.
Sometimes it's called benefit cost analysis.
