❓ 题目 According to the passage, which of the following statements about keystone species is TRUE?
- A. A. Keystone species always occupy the top trophic level as predators.
- B. B. The removal of a keystone species may lead to a decrease in biodiversity.
- C. C. The concept of keystone species has been universally accepted without criticism.
- D. D. Keystone species are typically abundant and have large biomass.