❓ 質問 According to the passage, what was the primary finding of Robert Paine's experiments?
- A. A) Physical environmental factors were the main determinants of community structure.
- B. B) The removal of a starfish predator caused a decrease in species diversity due to mussel dominance.
- C. C) Competition among species at the same trophic level was the most important factor in community organization.
- D. D) Keystone species are typically the most abundant organisms in an ecosystem.