Hashing is a reversible process.

• A. TRUE
• B. FALSE
• C. Not determinable
• D. Sometimes

Answer: (B)

Hashing is a one-way function. It converts input data of any size into a fixed-length digest, and while it’s quick to compute the hash from the input, reliably recovering the original input from that hash is not feasible with current methods. This preimage-resistance is what makes hashing useful for integrity checks and for securely storing passwords (often with a salt to prevent precomputed attacks). If someone only has the hash, they would generally have to guess inputs and compare their hashes, or use targeted attacks, rather than directly reversing the hash to get the original data. The existence of collisions or the ability to perform brute-force or rainbow-table attacks doesn’t change the fundamental non-reversibility; it just means there are practical ways to find inputs that produce the same hash or to guess the input more efficiently in some cases. So the statement that hashing is reversible is not correct.