Match List I with List II.
| List I | List II |
|---|---|
| A. Robert May | I. Species-Area relationship |
| B. Alexander von Humboldt | II. Long term ecosystem experiment using out door plots |
| C. Paul Ehrlich | III. Global species diversity at about 7 million |
| D. David Tilman | IV. Rivet popper hypothesis |
Choose the correct answer from the options given below:
May — 7 million species; Humboldt — species-area; Ehrlich — rivet-popper; Tilman — long-term plots.