Answer:
The best defense against all germs would be vaccination.
Vaccines are specifically designed to stimulate the immune system to recognize and defend against specific pathogens (bacteria, viruses, etc.). They are a highly effective way to prevent many infectious diseases and provide immunity against a wide range of germs. Vaccination helps protect individuals and can also contribute to herd immunity, reducing the spread of diseases within communities.
Cleanliness is essential for preventing the spread of germs but may not protect against all germs, as some are highly contagious or can survive in various environments. Antibiotics are effective against bacterial infections but do not work against viruses or other pathogens. Isolation can help prevent the spread of germs in certain situations, but it is not a comprehensive defense against all germs, and it may not be practical or necessary in many cases.