The correct option is
B Pneumonia
Humans produce droplets of saliva or mucus in various ways such as sneezing, coughing, speaking, etc. These droplets vary in size. Large droplets (> 5 µm) tend to settle to the ground rapidly. Droplets smaller than 5 µm are referred to as droplet nuclei and may remain suspended in the air for longer periods.
Pneumonia is a disease caused by the bacteria Streptococcus pneumoniae or Haemophilus influenzae. The pathogens attack and destroy the alveoli in the lungs causing inflammation that results in accumulation of fluid or pus in the lungs. This results in difficulty in breathing and other symptoms such as cough, fever, chills, etc.
Pneumonia spreads by droplet infection. A healthy person acquires the infection by inhaling the droplets released by an infected person through coughing or sneezing. Sharing of objects with an infected person can also lead to disease transmission as these objects will have deposits of the released droplets.
Cholera (caused by Vibrio cholerae), Typhoid (caused by Salmonella typhi) and Bacillary dysentery (caused by Shigella sp.) are enteric diseases that are spread by contaminated food and water (faecal-oral route transmission).