Assertion : In recent years ex situ conservation has advanced beyond keeping threatened species in enclosures.
Reason : Biodiversity knows no political boundaries and its conservation is therefore a collective responsibility of all nations.
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.