Final answer:
The contrast with Estonia is most likely included to highlight it as the nation that has officially embraced online voting, offering a real-world example against concerns of other states.
Step-by-step explanation:
Based on the provided context, the most likely reason the author includes the contrast with Estonia is B) to highlight the only nation to officially embrace online voting. Estonia serves as a counterexample to other states' hesitations regarding online voting due to concerns about security and voter fraud. As many states are cautious about adopting online voting, mentioning Estonia provides a real-world example of a country that has successfully integrated technology into its electoral process.