Correct choice is (c) Penicillium camembertii
To explain I would say: Ripening of cheese is carried out with the help of specific microbes. For example, Camembert cheese is ripened with the help of Penicillium camembertii. Roquefort cheese and Swiss cheese are ripened with the help of Penicillium roquefortii and Propionibacterium sharmani respectively.