Which of the following is the science of hiding information to protect sensitive information and communications from unauthorized access?

The correct answer is the science of cryptography, which involves techniques and methodologies used to secure information and communications by transforming data into a format that cannot be understood by unauthorized users. Cryptography encompasses a variety of practices, including encryption, where plaintext data is converted into ciphertext and only authorized parties with the correct decryption keys can access the original information.

This practice is crucial for safeguarding sensitive data during storage and transmission, ensuring confidentiality and integrity. It plays a significant role in various security protocols, such as SSL/TLS for secure web transactions and VPNs for secure connections.

Other options presented do not fit the definition provided in the question. For example, social engineering involves manipulating individuals to gain confidential information, rather than hiding information. DDoS (Distributed Denial of Service) refers to attacks aimed at overwhelming a system to disrupt services, which is not related to the concealment of information. Phishing is a technique used to deceive individuals into providing sensitive information by pretending to be a trustworthy entity, rather than using scientific methods of protecting communication through encryption.