Which of the following is a possible reason for the disappearance of the plant Silphium?

• A. A sudden increase in Silphium's reproductive rate
• B. Increased resistance to disease in Silphium populations
• C. Introduction of Silphium to new continents where it thrived
• D. Overharvesting by humans for medicinal and culinary uses

Answer: (D)

Verified step by step guidance

1. Understand the context of the problem: The question is asking about the possible reason for the disappearance of the plant Silphium. This requires analyzing the options provided and identifying the most plausible explanation based on biological and historical knowledge.
2. Evaluate the first option: 'A sudden increase in Silphium's reproductive rate.' A sudden increase in reproductive rate would likely lead to a population boom, making it less likely for the plant to disappear. This option does not align with the disappearance of the species.
3. Evaluate the second option: 'Increased resistance to disease in Silphium populations.' Increased resistance to disease would make the plant more resilient and less likely to disappear. This option is also inconsistent with the disappearance of the species.
4. Evaluate the third option: 'Introduction of Silphium to new continents where it thrived.' If Silphium thrived in new environments, it would not have disappeared. This option does not explain the disappearance of the plant.
5. Evaluate the fourth option: 'Overharvesting by humans for medicinal and culinary uses.' Overharvesting is a well-documented cause of species decline and extinction, especially for plants with high demand for their medicinal or culinary properties. This is the most plausible explanation for the disappearance of Silphium.