Identity the disease which is characterized by the following symptoms:

A. Alveoli filled with fluid
B. Fever chills headache
C. Coughing

Pneumonia (caused by Streptococcus pneumonia and Haemophilus influenza)

Mode of infection: By inhaling the droplets/aerosols released by an infected person.

Pathway: Entry of pathogen in respiratory tract $\to$ Infection of alveoli $\to$ Alveoli get filled with fluid $\to$Severe breathing problems.

Sign and symptoms: Fever, chills, cough, and headache. Lips and fingernails may turn grey to bluish in severe cases.