The evolution of C4 photosynthetic system is probably one of the strategies for:
| 1. | maximizing the availability of oxygen in spite of continuing high amount of water loss |
| 2. | maximizing availability of water in spite of continuing high amount of carbon dioxide loss |
| 3. | reducing the amount of water loss but leads to decreased availability of carbon dioxide |
| 4. | maximizing the availability of carbon dioxide while minimizing water loss |