Which of the following cryptography attack methods is usually performed without the use of a computer?

A ciphertext-only attack involves statistically analyzing intercepted ciphertext to deduce the plaintext or key, which typically requires computational tools to process the data.

A chosen key attack involves selecting and testing specific key values against encrypted data to find the correct key, a process that requires computational assistance.

A rubber hose attack is a non-technical attack in which an adversary obtains encryption keys or passwords by physically coercing, threatening, or torturing the keyholder. Because the 'attack surface' is human psychology and physical vulnerability rather than computational analysis of ciphertext, it is performed entirely without a computer.

A rainbow table attack uses precomputed hash-to-plaintext lookup tables that must be stored on and searched with a computer to reverse password hashes.