Of Nitrogen and Phosphorus, Which Is the Most Limiting Nutrient

Of nitrogen and phosphorus, which is the most limiting nutrient to primary production early in primary succession, and why?

A) Phosphorus, because it undergoes occlusion over time
B) Nitrogen, because it undergoes chemical reactions with the phosphorus
C) Nitrogen, because it takes a long time to accumulate in the soil through decomposition
D) Phosphorus, because it is very soluble and is easily leeched from the soil