In General, Given Sufficient Precipitation, What Relationship Does NPP Show

Multiple Choice

In general, given sufficient precipitation, what relationship does NPP show to latitude?

A) NPP is highest at low (equatorial) latitudes and decreases at high latitudes.
B) NPP is highest at high latitudes and decreases at low (equatorial) latitudes.
C) NPP is relatively equal at all latitudes; it varies with nutrients, not latitude.
D) NPP is relatively equal at all latitudes; it varies with temperature, not latitude.
E) NPP is variable with respect to latitude; high and low NPPs occur at all latitudes.