Without the ability to view the image you mentioned, I can suggest possible answers based on common environmental challenges in Southeast Asia that might be related to activities in the region.
If the activity depicted is related to human actions such as logging or urban development, the most directly related environmental challenges could likely be:
1. **deforestation** - This is often a result of land clearing for agriculture or urbanization.
2. **flooding** - Deforestation and urbanization can lead to increased runoff and reduced natural flood control, contributing to flooding.
If the activity shown involves natural geological processes, then the correct answers might include volcanic activity or earthquakes.
If you can provide more details about the activity shown in the image, I can offer a more precise answer!