Which of the following encryption methods provides confidentiality but not integrity?

The correct answer is symmetric encryption, which is designed primarily to ensure confidentiality through the use of shared secret keys for encrypting and decrypting data. When a sender encrypts data with a symmetric algorithm using a shared key, the recipient who possesses the same key can decrypt the data to retrieve the original plaintext. This process effectively ensures that unauthorized parties cannot access the content, thus maintaining confidentiality.

However, symmetric encryption does not inherently provide integrity, which is the assurance that the data has not been altered in any unauthorized manner. While symmetric encryption can prevent unauthorized access to the data, it does not verify whether the decrypted data is the same as the original data sent by the sender. Integrity measures typically require separate mechanisms, such as cryptographic hash functions or message authentication codes (MACs), which are often used in combination with encryption to ensure both confidentiality and integrity.

In summary, symmetric encryption is effective for protecting the confidentiality of information, but on its own, it does not guarantee that data remains intact or unmodified during transmission or storage.