Organisms very sensitive to sulphur dioxide levels, used as air pollution indicators, are:
- Ferns
- Algae
- Lichens
- Mosses
Show answer and solution
Correct answer: C. Lichens
1. They grow as a greenish-white crust on bark.
2. Lichens vanish where sulphur dioxide is high.
3. Compare trees near roads and away from them.
_Source: syllabus Science, Chapter 14, Natural Resources._