spraying insects with a pesticide ddt causes some pesticide resistance in insect populations.The changes that occur in the insect population are related to a pattern in genetic inheritance. Repeated spraying kills many insects; however, more frequent spraying and higher concentrations fail to kill insects. In this environment, the spaying of insects appears to act as
SELECT ONE:
A. BIOLOGICAL FACTOR
B.GROWTH INHIBITOR
C.AN AGENT OF SELECTIVE PRESSURE
D. AN AGENT TO ELIMINATE OLD WEAK INSECTS