How does encryption improve online security?

Encryption plays a crucial role in enhancing online security by transforming data into a coded format, which makes it unreadable to anyone who does not possess the appropriate decryption key. This process effectively safeguards sensitive information, such as personal details, financial transactions, and confidential communications, from unauthorized access. When data is encrypted, even if it is intercepted during transmission, it would appear as a jumble of characters rather than intelligible information. This significantly reduces the risk of data breaches and cyberattacks, as only authorized users who have the decryption key can access the original data.

In contrast, the other options do not accurately describe how encryption functions or its implications for security. Sending data without charge does not relate to encryption and instead pertains to costs associated with data transmission. Reducing file size is related to data compression techniques rather than encryption, which focuses on protecting data integrity. Making data easily accessible is contrary to the purpose of encryption, which aims to restrict access to safeguard sensitive information.