WAEC Agricultural Science 1992 Question 2

The principles involved in crop production include the following, I. controlling of diseases, weeds and pests, II. maintaining the quality of agricultural produce, III. conserving and preserving of natural resources, IV. controlling soil erosion. Which of the following combinations does the government aim at when making agricultural policies?

1. A.I and II only
2. B.III and IV only
3. C.I, II and III only
4. D.I, II, III, and IV
5. E.II, III and IV.