Which of the following nutrients is available at neutral pH value?

Phosphorus is a nutrient that is available at a neutral pH value.
Precipitation of phosphorus as slightly soluble calcium phosphates occurs in calcareous soils with pH values around 8.0.
Under acid conditions, phosphorus is precipitated as Fe or Al phosphates of low solubility. Maximum availability of phosphorus generally occurs in a pH range of 6.0 to 7.0.