Which statement about encryption types is true?

Which statement about encryption types is true?

• A. Asymmetric encryption uses a single shared key to encrypt and decrypt.
• B. Symmetric encryption uses a public key to encrypt and a private key to decrypt.
• C. Symmetric encryption uses a single shared key to encrypt and decrypt data.
• D. Asymmetric encryption uses no keys.

Answer: (C)

Symmetric encryption uses a single shared key to encrypt and decrypt data. Both parties must possess the same secret key, and that same key is used for both directions of the operation. This approach is fast and efficient for handling large volumes of data, which is why algorithms like AES are common for bulk encryption. In contrast, asymmetric encryption uses a pair of keys: a public key for encryption and a private key for decryption. The public key can be shared openly, enabling secure communication without previously sharing a secret key, while the private key stays secret to the owner. This setup is heavier computationally, which is why it’s often used for key exchange or digital signatures rather than bulk data encryption. So the true statement is that symmetric encryption uses a single shared key to encrypt and decrypt data. The other descriptions mix up which keys are used or mistakenly claim no keys are involved.

Symmetric encryption uses a single shared key to encrypt and decrypt data. Both parties must possess the same secret key, and that same key is used for both directions of the operation. This approach is fast and efficient for handling large volumes of data, which is why algorithms like AES are common for bulk encryption.

In contrast, asymmetric encryption uses a pair of keys: a public key for encryption and a private key for decryption. The public key can be shared openly, enabling secure communication without previously sharing a secret key, while the private key stays secret to the owner. This setup is heavier computationally, which is why it’s often used for key exchange or digital signatures rather than bulk data encryption.

So the true statement is that symmetric encryption uses a single shared key to encrypt and decrypt data. The other descriptions mix up which keys are used or mistakenly claim no keys are involved.