Which of the following can result from a collision?

Producing the same digest as a different message is a key concept in cryptography, particularly in the context of hashing algorithms. A collision occurs when two distinct inputs produce the same hash output, which is also referred to as a digest. This phenomenon is typically undesirable in secure hashing functions because it undermines the reliability and integrity of the hash function. For instance, in digital signatures and other security applications, if two different messages yield the same digest, an attacker could potentially substitute one message for another without detection, leading to security vulnerabilities.

In contrast, understanding the original message, creating a secure encryption key, and eliminating data redundancy do not relate to the effects of a collision. These concepts involve other aspects of information security and data encryption that do not directly tie to the implications of hash collisions. Thus, option B accurately represents the consequences that can arise from a collision in the context of cryptographic hashing.