The correct option is
C Somatic hybridisation
Hybridoma is a somatic cell hybrid formed by fusion of normal lymphocytes and tumor (lymphoma) cells. B cell hybridomas are the most useful source of monoclonal antibodies; the hybridoma cells are able to produce antibody like the normal parent and proliferate indefinitely in culture like the parent tumor cells
So, the correct answer is 'Somatic hybridisation'