In a recent experiment, a spider breed was chosen as a potential natural pesticide to reduce the numbers of a certain insect that is very harmful specifically to growing watermelons. In an average infested watermelon field, tagged spiders were released, and their feeding monitored for a month. Results of the experiment showed that although the spiders ate extremely well, the number of pests remained the same as the month before. Therefore, the spiders must have eaten other insects and not their intended prey.
Which of the following would it be most useful to establish in order to evaluate the argument?
A. Whether the harmful insect is preyed upon by any other predators, be they insects or small creatures
B. Whether the particular breed of spider chosen also causes harm to watermelons due to its nesting
C. Whether the number of spiders equalled the number of watermelon pests after one month
D. Whether the field already contained spiders that perhaps prey upon the watermelon pests
E. Whether previous population figures for the watermelon pest show an increase over time
OA E
Source: Economist Gmat
Which of the following would it be most useful to establish in order to evaluate the argument?
A. Whether the harmful insect is preyed upon by any other predators, be they insects or small creatures
B. Whether the particular breed of spider chosen also causes harm to watermelons due to its nesting
C. Whether the number of spiders equalled the number of watermelon pests after one month
D. Whether the field already contained spiders that perhaps prey upon the watermelon pests
E. Whether previous population figures for the watermelon pest show an increase over time
OA E
Source: Economist Gmat
