Which Statement About Roots and Root NPP Is False

Which statement about roots and root NPP is false?

A) Root NPP is more difficult to estimate than aboveground NPP because roots turn over more slowly.
B) The smallest roots are the most likely to turn over.
C) Roots do not transfer carbon to symbionts.
D) In order to accurately measure root NPP with harvest methods, roots must be harvested more frequently than aboveground biomass.