Biologist: The recent increase in the population of deer in suburban areas is primarily due to the decline in their natural predators, such as wolves and cougars, which have been driven out by human expansion. Therefore, to control the deer population and prevent overgrazing, reintroducing these predators into suitable habitats is the most effective solution.
- AMany of the suitable habitats for wolves and cougars have been fragmented by suburban development, limiting their ability to establish stable territories.
- BDeer populations in areas without natural predators have remained stable due to other environmental factors.
- CSuburban deer populations thrive partly because of abundant food sources from gardens and landscaping, and reduced hunting pressure.
- DThe reintroduction of large predators often leads to conflicts with human residents and livestock.
Show answer & explanationAnswer & explanation
Correct answer: C. Suburban deer populations thrive partly because of abundant food sources from gardens and landscaping, and reduced hunting pressure.
The biologist attributes the deer increase *primarily* to predator decline and proposes predator reintroduction as the *most effective solution*. Option C introduces significant alternative causes for the deer population increase (abundant food, reduced hunting pressure). If these factors are also major contributors, then the decline in predators is not the *sole* or *primary* cause, and reintroducing predators might not be the *most effective* or only solution, thereby weakening the conclusion.
Why the other options are wrong
- A. This points to a practical difficulty in implementing the proposed solution (reintroduction), but doesn't challenge the underlying causal claim about predator decline or the *effectiveness* if reintroduction *were* successful.
- B. This directly contradicts the biologist's premise about predator decline being the primary cause, serving as a strong weakening factor.
- D. This points to a practical difficulty or negative consequence of the proposed solution, but doesn't directly challenge the *causal link* between predator decline and deer increase, or the *effectiveness* of reintroduction in controlling deer.
Undermining a Primary Cause
Undermining a primary cause involves introducing information that suggests the proposed cause is not the *main* or *sole* reason for an observed effect, or that other factors are equally or more influential, thus weakening the causal argument.
- Challenges the uniqueness or dominance of the identified cause.
- Presents other significant contributing factors.
- Often used in 'most weakens' questions to find the strongest alternative.
Memory trick: The 'main' villain might have a powerful accomplice you didn't see.