Assertion : estimate given by IUCN for biodiversity do not give any figures for prokaryotes.
Reason : Biologists are not sure about how many prokaryotic species there might be.
A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.