Darwin Found That Many Different Species of Finches Were Found

Darwin found that many different species of finches were found on the Galapagos Islands and nowhere else.The finches were related to a species found on the mainland of South America.From this he concluded:

A) ancestral species originated on the Galapagos Islands and some migrated to the mainland.
B) separate acts of creation put some species on the islands and some on the mainland.
C) an ancestral species migrated from the mainland and diverged over time into separate species on the islands.
D) an ancestral species migrated to both South America and the Galapagos Islands from Europe and then diverged into separate species.