WAEC Agricultural Science 1992 Question 35

Which of the following is not an aim of improving crops?

1. A.Producing crops which are resistant to diseases and pests
2. B.Producing crops which are adapted to adverse weather conditions
3. C.Increasing yield by planting high yielding and vigorous varieties
4. D.Improving the qualities of farm produce
5. E.Improving mechanical method of harvesting crops.