❓ Câu hỏi According to the passage, what is one major reason why ecosystem services are often undervalued?
- A. A) They are difficult to quantify in terms of their ecological impact.
- B. B) They are typically provided as public goods, leading to overuse.
- C. C) They are only available in remote and inaccessible regions.
- D. D) They have been historically excluded from scientific research.