- Active volcanoes are most common along tectonic plate boundaries
- Earthquakes are most common along tectonic plate boundaries
- Therefore, active volcanoes and earthquakes are most common along tectonic plate boundaries

- "A hot substance is a source of heat" is not relevant

Hence, active volcanoes and earthquakes are most common along tectonic plate boundaries
Q: Many processes on Earth occur at or near tectonic plate boundaries. Which geological events are most common along tectonic plate boundaries?
Context:
- Active volcanoes are most common along tectonic plate boundaries 
- A hot substance is a source of heat
- Earthquakes are most common along tectonic plate boundaries