How many sharing sets can be created per user per object?

The correct answer highlights that only one sharing set can be created per profile per object. This means that for each user profile associated with a specific object, Salesforce allows the creation of a single sharing set to manage access to records of that object based on the user's role within the community.

This design maintains streamlined governance over data access, ensuring clarity in permission management for users sharing similar roles and responsibilities. When a user profiles are well-structured and sharing sets are effectively utilized, organizations can enforce data security and accessibility effortlessly.

The limitation of one sharing set per profile per object balances operational efficiency and security by preventing overly complex configurations that could arise from multiple sharing sets. It allows for focused management of access rights, ensuring that users only have the access necessary for their role within the community.

In contrast, other choices suggest either multiple sharing sets or a varying number of sharing sets that could complicate the paradigm of access control and lead to potential data exposure or mismanagement.