A healthy person can acquire pneumonia in which of the following ways?

The correct answer is Option (4) → Both (1) and (2)

Pneumonia is caused by bacteria such as Streptococcus pneumoniae and Haemophilus influenzae, which infect the alveoli of the lungs. It is an air-borne disease. A healthy person picks it up from the droplets an infected person releases, or from things the infected person has used.

Option (1) By inhaling droplets/aerosols released by an infected person — Correct statement, but it is only one of the ways. Droplets and aerosols released by an infected person carry the bacteria, and a healthy person who inhales them gets the infection.

Option (2) By sharing glasses and utensils with an infected person — Correct statement, but it is only one of the ways. The infection can also spread by sharing glasses and utensils with an infected person.

Option (3) By drinking water contaminated with the faecal matter of an infected person — Incorrect. Water contaminated with faecal matter spreads diseases of the gut such as amoebiasis, and typhoid spreads through contaminated food and water. Pneumonia infects the lungs and is not acquired by drinking such water.

NCERT Extract:
Common Diseases in Humans – “… Bacteria like Streptococcus pneumoniae and Haemophilus influenzae are responsible for the disease pneumonia in humans which infects the alveoli (air filled sacs) of the lungs. As a result of the infection, the alveoli get filled with fluid leading to severe problems in respiration. The symptoms of pneumonia include fever, chills, cough and headache. In severe cases, the lips and finger nails may turn gray to bluish in colour. A healthy person acquires the infection by inhaling the droplets/aerosols released by an infected person or even by sharing glasses and utensils with an infected person.”