The microorganisms that live in symbiotic association in lichens are

Question

$\begin{array}{1 1} (a)\; \text{Fungus and Protozoa} \\ (b)\; \text{Bacteria and Protozoa} \\ (c)\; \text{Algae and Bacteria} \\ (d)\; \text{Algae and Fungi} \end{array}$