2. Scientists have discovered an unusual diamond from the mantle that
encased hydrous ringwoodite. This is the first and only ringwoodite
specimen from the mantle scientists have ever analyzed. Though the find
suggests the mantle could contain a lot of water, what is the main
problem with this evidence?

A. The ringwoodite was contaminated by the process used to extract it
from the earth.
B. The sample was found inside diamond, so it can not really be
ringwoodite.
C. The sample size is too small and may not be representative of mantle
ringwoodite.
D. Scientists are not able to extract minerals from the mantle, so this is
not a true sample.