Question

Litmus is obtained from lichen

• A. Lecanora esculenie
• B. Roccella tinctoria
• C. Cladonia rangiferina
• D. Cetraria islandica

Answer 1

The correct option is B Roccella tinctoria

Litmus is a blue dye extracted from various species of lichens. Although these lichens grow in many parts of the world, almost all litmus is extracted and packaged in Holland. Litmus is red at pH 4.5 and blue around pH 8.3. While most litmus is used to make litmus papers, some is used as a colouring for beverages. Litmus is obtained from certain lichens, especially Rocella tinctoria.

Thus, the correct answer is option B.