Which of the following statements is incorrect?
(a) Lichen, an association of fungus and algae is an example of mutualism
(b) Those epiphytes which use other plants for support only and not for water or food supply and are examples of commensalism.
(c) Sea-anemone on hermit-crab is an example of protocooperation
(d) Mutualism, protocooperation, commensalism cannot be included under symbiosis.