What is the physiopathology of acute obstructive laryngitis?

The PI virus affects first the epithelial cells of the nasopharynx and then progresses to the ciliated cells of the respiratory epithelium of the proximal and distal airway.
The host's response to viral infection involves innate and acquired response with production of interferon, IgA, CD4/CD8 response and IgG production.
The virus has a direct cytopathic effect on the respiratory epithelium.
The result of the process is an inflammation of the airway with greater intensity at the level of the larynx and trachea, especially in the subglottic space.
a) I and II are correct.
b) II and IV are correct.
c) I, II and IV are correct.
d) II, III and IV are correct.