Self-study
Although there are immediate short-term gains in crop yield from a single application of certain hydrocarbon-based pesticides to fields on which they have not been previously used, studies have shown clearly that long-term use gradually depresses crop yield from this initially elevated level. ██ ██████ ████████ ████ ███ ██ █████ ██████████ ████████
Summary
Using certain hydrocarbon-based pesticides on a field not previously treated with pesticides results in immediate short-term increases in crop yield. However, long-term use results in a decrease in crop yield over time.
Strongly Supported Conclusions
Use of these pesticides results in benefits that decrease over time.
3.
Which one of the following █████ ████ █████████ ████████ ███ ████████ ██████
a
is uneconomic
This answer is unsupported. Nothing in the stimulus suggests that using pesticides causes an overall financial loss. We know there's a short-term gain, and we don't know whether the long-term decrease is enough to neutralize that gain.
b
damages the environment
This answer is unsupported. The stimulus does not give us any information about whether the pesticides damage the environment.
c
will eventually make ████ ████████ ████████████
This answer is unsupported. The stimulus does not give us any information about whether the pesticides can ever worsen pest problems, much less make them "unmanageable."
d
is probably not █████████ ██ ██████████ ████ ██████████████ ████████████
This answer is unsupported. The stimulus does not give us any information about the manufacturers’ instructions.
e
gives financial returns ████ ████████ ████ ████
This answer is strongly supported. When crop yields are elevated after the first use, financial returns also increase. As crop yields decrease over time with long-term use, so do the financial returns.