Which of the following is a key feature of encryption?

A key feature of encryption is that it converts data into an unreadable format. This process is essential for protecting sensitive information by transforming it into ciphertext, which is not comprehensible without the appropriate decryption key or method. Thus, even if an unauthorized party gains access to the encrypted data, they cannot understand or use it without the means to decrypt it.

In the context of data security, this feature is fundamental because it ensures confidentiality and protects information from unauthorized access, thereby reducing the risk of data breaches. Encryption is widely used in various applications, including securing communications over the internet, protecting personal data on devices, and safeguarding sensitive information stored in databases.

Other options do not accurately reflect the primary purpose of encryption. For example, unrestricted access to data contradicts the very aim of encryption, which is to restrict access to only those authorized to view the data. Data compression pertains to reducing file sizes, which is unrelated to encryption, while boosting connection speeds does not align with the goals of encryption as it focuses on securing data rather than enhancing performance. Thus, the correct answer accurately encapsulates the fundamental role of encryption in data protection.