The correct option is A Culex - Filariasis
Yellow fever is an acute viral disease and it primarily spreads by mosquitoes of Aedes aegypti species. Typhoid is bacterial infection caused by Salmonella typhi. Plague is caused by enterobacteria carried by small rodents. Culex is the genus of mosquitoes and serves as vectors and filariasis is one such disease for which Culex is the vector.
Thus, the correct answer is option (A), 'Culex - Filariasis'.