The adaptations that allow bacteria to live on the International Space Station (ISS) include:
- Living in an environment with increased radiation levels: Bacteria that can tolerate or repair damage from radiation are better equipped to survive in the high-radiation environment of space.
Bacteria may not have specific adaptations related to increased oxygen levels, increased carbon dioxide levels, or increased water levels in the context of the ISS, as the conditions can be quite controlled on the station compared to Earth's varying environments. However, certain bacteria can adapt to various atmospheric compositions, but those specific adaptations are not highlighted in this context.
Therefore, the correct answer is:
- living in an environment with increased radiation levels.