Smallpox can spread from one person to another by the following routes:

The correct answer encompasses all the ways smallpox can be transmitted between individuals. Smallpox is primarily spread through direct contact with infected individuals, as the virus is present in the lesions and body fluids of those infected. Additionally, respiratory droplets play a significant role in transmission when an infected person coughs or sneezes, allowing the virus to enter the body through the nasal or oral mucosa of another individual. Lastly, contaminated surfaces can also harbor the virus for a period, posing a risk if a person comes into contact with these surfaces and then touches their face or mucous membranes. This multifaceted approach to understanding how smallpox spreads highlights the critical need for rigorous hygiene practices and appropriate public health measures during outbreaks.