The answer is letter B.
A communicable disease is a disease that
can be passed from person to person. It can also occur from an animal to a
person or vice versa. Airborne viruses, bacteria, blood, and bodily fluids can
cause the spread of these diseases. When things are infectious or contagious it
also refers to communicable diseases. The most common communicable disease is
the flu, which can easily spread in an enclosed environment with a recycled
circulating air (e.g. air-conditioning). Infectious disease caused by blood
contact like HIV/AIDs are also dominant in society.