What was the most likely way the classical swine fever virus spread to different sites during the outbreak in the U.K.?

The spread of the classical swine fever virus during the outbreak in the U.K. is most likely attributed to the movement of infected animals, including both domesticated pigs and, to some extent, wildlife scavengers that may have carried dead infected animals to neighboring farms. This transmission route highlights the interconnectedness of animal populations and the pivotal role that livestock movement plays in disease dissemination.

In commercial farming scenarios, the movement of infected pigs between farms, often for trade, can introduce pathogens to new environments, facilitating outbreaks. Additionally, scavengers consuming infected carcasses can be a significant vector for disease transmission, as they may carry the virus on their bodies or excreta and spread it to other areas.

While feeding infected pig swill could also pose a risk, the specific outbreak dynamics and the key role that direct animal movement played suggest that option C provides a more complete understanding of how the virus likely traveled between farms. The concern with wild boar or feral pig populations, while relevant in the context of other infectious diseases, was less significant in this specific outbreak scenario as reflected by historical data.