To answer this question, we need to understand the concept of mappings and sessions.
In computer science and programming, a mapping refers to the association or relationship between two sets of elements. In the context of sessions, a session is a period of interaction between a user and a computer system.
Based on this information, the correct answer is:
Option A) one - This option is correct because a session can have only one mapping. During a session, there is typically one-to-one mapping between a user and the computer system, allowing for a single user to interact with the system at a time.
Option B) two - This option is incorrect because a session cannot have multiple mappings. Only one user can be directly associated with a session at a time.
Option C) many sessions - This option is incorrect because it refers to the number of sessions, not the number of mappings per session.
Option D) three - This option is incorrect because a session can have only one mapping.
Therefore, the correct answer is A) one.