transmission of acquired characteristics. use or disuse of their beaks. natural mutagens. natural selection.
I gave my students this multiple choice question: According to Darwin's theory of evolution, the variations among finches that he observed in the Galapagos Islands resulted from

Only one answer is correct among these 4 choices:
- transmission of acquired characteristics.
- use or disuse of their beaks.
- natural mutagens.
- natural selection.

Could you tell me which one is correct?

natural selection.