5. The passage most strongly suggests that a plant would most likely not be a source of rubber if it
Answer: C
A plant would most likely not be a source of rubber if it evolved in areas where herbivorous insects are not very common.
The passage suggests that rubber plants evolved their rubber-producing capabilities as a defense mechanism against herbivorous insects. Therefore, a plant that evolved in an environment with few herbivorous insects would have less evolutionary pressure to produce rubber, making it less likely to be a viable source of rubber.
A) lacked resistance to diseases that afflict trees traditionally used for rubber
While resistance to diseases is important for the sustainability of rubber production, the passage does not indicate that this trait is essential for a plant to be a rubber source. The primary focus is on the evolutionary benefits of rubber production in response to herbivorous insects, not disease resistance.
B) could not compete successfully with guayule in desert locales
Competition with guayule is not presented as a determining factor for a plant's viability as a rubber source. The passage emphasizes the evolutionary context linked to herbivorous insects rather than competitive success in specific environments, making this option less relevant.
C) evolved in areas where herbivorous insects are not very common
This option aligns perfectly with the passage’s argument that rubber evolution is closely tied to the presence of herbivorous insects. A plant in an environment with few such insects would lack the evolutionary drive to produce rubber, thereby making it less likely to be a source of rubber.
D) possessed allergenic proteins
The presence of allergenic proteins is mentioned in context with guayule, which produces rubber free of such proteins, making it a desirable alternative. However, this does not disqualify other plants from being a rubber source. The passage does not suggest that allergenic proteins would prevent rubber production.
E) was generally not considered to be a weed
The classification of a plant as a weed is irrelevant to its ability to produce rubber. The passage does not discuss weed status as a factor in rubber production, focusing instead on evolutionary adaptations related to herbivorous insects.
Conclusion
The evidence from the passage clearly supports option C, as it directly connects the evolution of rubber production to the presence of herbivorous insects. Other options either misinterpret the key factors influencing rubber production or are not addressed in the context of the passage, reinforcing that C is the most logical conclusion.