Why was smallpox an ideal candidate for eradication?

1. It was passed directly through people.

2. Distinctive symptoms

3. People were only at risk when in the presence of an infected person with obvious and clear symptoms.

Explanation:

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answer:

it could come from a variety of sources.

explanation:

..although it was most likely developed through zoonotic transmission, where an infectious disease which usually afflicts when animals jump to humans.