- A. Cholera is primarily a water-borne disease (IV), caused by the bacterium Vibrio cholerae, typically spread through contaminated water. - B. Filaria (Filariasis) is a vector-borne disease (III), transmitted by mosquitoes carrying filarial worms. - C. Tuberculosis (TB) is an airborne disease (I), caused by Mycobacterium tuberculosis bacteria that spread through the air when infected people cough, sneeze, or talk.