❓ 题目 According to the passage, which of the following is a reason why ecosystem services are often overexploited?
- A. A. They are usually provided by private companies that seek profit.
- B. B. Their public-good nature leads to market prices that do not reflect full social costs.
- C. C. Governments are unable to regulate the use of natural resources.
- D. D. Scientists have not yet developed methods to measure their value.