The factor that would be expected to have the greatest impact on primary productivity is:
c. solar energy
Explanation:
1. Primary productivity is the rate at which energy is converted by photosynthetic and chemosynthetic autotrophs into organic substances.
2. Solar energy is the primary source of energy for photosynthesis in most ecosystems.
3. Without solar energy, plants and other photosynthetic organisms would not be able to carry out photosynthesis, which is crucial for their growth and productivity.
4. Nutrient availability, chemical energy, and water availability are important for plant growth, but solar energy is the driving force behind primary productivity in most ecosystems.
Therefore, solar energy would have the greatest impact on primary productivity among the options provided.
