Certified Information Security Manager (CISM) Practice Exam 2025 – The All-in-One Guide to Mastering Certification Success!

Hash functions are designed to take an input (or message) of any length and produce a fixed-size output, known as a hash value or digest. This characteristic is fundamental to the nature of hashing algorithms. Regardless of whether the input message is short or long, the output remains consistent in size. Therefore, it is precisely this uniformity of output size that makes option C the correct answer.

The length of the hashing algorithm itself, the type of encryption method, and the size of the encryption key do not define the nature of the output from the hash function. Instead, hash functions are distinct from encryption functions, which are influenced by these factors. For instance, encryption methods depend heavily on keys for transforming the plaintext into ciphertext, while hashing is a one-way process that does not require any key.