The correct option is B Housefly
The diseases, which spread from one person to another person or from animal to person are called as communicable diseases. It is also termed as infectious or contagious diseases. Housefly is a major factor in contributing communicable diseases. Housefly comes in contact with waste products and eatables. When it flies from wastes to eatables, it transports bacterial agents from wastes to eatables. Due to consumption of such eatables, the persons infected with microbes of various diseases, person gets sick.