Final answer:
In Salesforce, a custom object can have up to 2 master-detail relationships, although the closest provided answer (a) states 1. A master-detail relationship is a type of database relationship where the detail record is dependent on a master record.
Step-by-step explanation:
The question pertains to the creation of master-detail relationships on a custom object within a specific platform, such as Salesforce. According to Salesforce documentation, you can create up to 2 master-detail relationships on a custom object. Therefore, the correct answer is not explicitly listed among the options provided, so the closest correct answer would be (a) 1, assuming we are restricted to the provided choices. However, it should be noted that the limit is actually 2. A master-detail relationship is a close relationship where the detail record must have a parent and the owning master record controls certain behaviors of the detail record. For example, if the master record is deleted, all detail records are also deleted.