Which of these actions is effective in improving online privacy?

Using encrypted email services is effective in improving online privacy because it ensures that the content of your communications is protected from unauthorized access. Encryption scrambles the email's content, making it unreadable to anyone who intercepts it without the decryption key. This is particularly important in the digital age, where data breaches and unauthorized surveillance are common. Encrypted email services help safeguard sensitive information, such as personal data, financial details, and confidential communication, making it much more challenging for hackers or third parties to access your private correspondence.

In contrast, signing up for newsletters may expose you to more sharing of your personal information with third parties, using only a standard search engine might not provide privacy-focused features that protect user data, and relying on public Wi-Fi can increase the risk of data interception and unauthorized access to sensitive information. Thus, opting for encrypted email services is a proactive measure that significantly enhances your online privacy.