Question

Which among the following is correct?

A.	Viroids	Infectious free RNA	Potato spindle tuber disease
B.	Prions	Infectious proteins	Mad cow disease
C.	Viruses	Nucleo proteins	Mumps
D.	Lichens	Algae + Fungi	Indicators of CO pollution

• A. A, B, C, D
• B. A, B, D
• C. Only A, C
• D. A, B, C

Answer 1

The correct option is D A, B, C

A, B and C are correct.
Lichens are a symbiotic interaction between algae and fungi, but they are not the indicators of carbon monoxide pollution. They are indicators of sulphur dioxide pollution. Lichens have efficient absorption systems that result in accumulation of sulphur when exposed to high sulphur dioxide concentration. The accumulated sulphur in lichens disrupts photosynthesis by algae and it affects reproduction and spore germination.