How does Rikki-tikki's decision not to destroy all Nagaina's eggs contribute to the story.

1. Nagaina leaves the garden after she learns that her eggs have been destroyed, which makes the garden safe again.
2. It makes the other animals turn on Rikki-tikki and refuse to help him defeat Nagaina.
3. When Nagaina is about to bite Teddy, Rikki-tikki is able to distract her telling her there is only one egg left.
4. Rikki-tikki successfully prevents the birth of future cobras, and this makes the family happy.