Custom Object attributes must be assigned to anAttribute Groupbefore Business Manager can expose them in the Custom Object editing interface. Defining an attribute creates its metadata, but grouping controls its administrative presentation.
Salesforce explicitly states that after creating custom-object attributes, developers must add them to an Attribute Group in order to manage the custom object through Business Manager. Salesforce also notes that the custom object ' s key attribute must be included in an attribute group; otherwise, administrators cannot create instances of the custom object definition through the Custom Object module.
Option A is unrelated. Changing the data type modifies how an attribute stores information and can even destroy existing values, but it does not solve the Business Manager visibility issue. Option C confuses attribute presentation with custom-object scope and replication. Site-specific storage determines where object instances exist, while replication configuration governs movement between instances; neither causes fields to appear in the editor.
The correct workflow is therefore to define the attributes, create the appropriate Attribute Group, assign the desired fields—including the key—to the group, and then manage object instances through the site ' s Custom Objects module.
Study Guide reference:Data Management Using Business Manager Usage — Custom Object Types, Attribute Definitions, Attribute Groups, Custom Object Editor, and Business Manager metadata.
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