Question

a cabbage farmer has a two - acre field of cabbage. each year, the crop is attacked by cabbage - eating beetles. to combat the problem, the farmer sprays her field with a mild pesticide. the pesticide kills 80% of the beetles each year. by 2020, the farmer needed 40 gallons of pesticide (she used only 15 gallons back in 1990) to control the same number of beetles. which of the following would best explain this increase in pesticide needed and demonstrate that beetle resistance developed over time?

a. the surviving beetles each year reproduced, creating a population increasingly resistant to the pesticide; testing the effectiveness of the same pesticide on offspring populations would confirm resistance.

b. the total number of beetles increased independently of resistance, so using more pesticide was necessary to kill the larger population; counting beetles each year would confirm this.

c. beetles changed their feeding behavior over time, making them less exposed to pesticide; observing beetle behavior in sprayed and unsprayed plots would confirm this.

d. environmental changes made the pesticide less potent over time; analyzing pesticide samples from different years would confirm degradation.

Explanation:

Answer:

A. The increasing dosage used each year selected, creating a population increasingly resistant to the pesticide; looking the effectiveness of the same pesticide on offspring populations would confirm resistance