Which recommendation is appropriate for meeting these requirements?

Get Cloudy Consulting has a custom Contract object that requires Org-Wide Defaults set to Private. The owner of the Contract record will be the Contract Origination Officer, and the Contract record must be shared with a certain Underwriter on a contract-by-contract basis. The Underwriters should only see the Contract records for which they are assigned.

Which recommendation is appropriate for meeting these requirements?
A . Create a master-detail relationship from the Contract to the User object. Contract records will be automatically shared with the Underwriter.
B . Use criteria-based sharing rules to share the Contract object with the Underwriter based upon the criteria defined in the criteria-based sharing.
C . Create an Apex Sharing Reason on the Contract object that shares the Contract with the Underwriter based upon the criteria defined in the Sharing Reason.
D . Create a lookup relationship from the Contract object to the User object. Use a trigger on the Contract object to create the corresponding record in the Contract Share object

Answer: B