Si, members A. B. C. D. E and F of a family are travelling together; 'B' is the son of 'C' but ·C" is not the mother of 'B'. 'A' and 'C' is a married couple. 'E' is the brother of 'C'. 'D' is a daughter of· A·. •f' is brother of 'B'. How many male members are there in the family?