Final answer:
Cloning
Step-by-step explanation:
The correct answer is C: Cloning. Duplicating the Electronic Serial Number (ESM) of one phone and using it in a second phone is known as cloning. This allows the perpetrator to have calls and other transactions billed to the original phone. Cloning involves copying the unique identifier of one phone and programming it into another phone, making it appear as if both phones have the same identifier.