Answer:
• Droplets
• Aerosol
• Contact
Explanation:
Causative agents of respiratory diseases are usually viruses but can be bacteria as well and they spread by various ways including contact, aerosol and droplets.
With contact, if one comes into contact with another person such that they inhale the causative agent, they will get the agent.
With aerosol, the causative agent will remain in the air when expelled by an infected person and when another person breathes them in, they infect that person as well. This method makes respiratory diseases particularly dangerous as they can spread through a large population fairly quickly.
Such agents can also be spread by droplets when a person comes into contact with the droplets that an infected person leaves. If these droplets somehow manage to be inhaled by another person, that person would get infected.
