Before application code can create or manipulate instances of a new custom-object type, the object ' smetadata definition must exist in B2C Commerce. Among the provided options, A represents that required first step.

More precisely, the developer creates aCustom Object Type definitionin Business Manager under Administration > Site Development > Custom Object Types. Salesforce documents that a custom object type must be defined before custom object instances can be created. The definition establishes the ID, key attribute, storage scope, replication behavior, custom attributes, and attribute groups.

Only after this metadata exists can code use APIs such asCustomObjectMgr.createCustomObject()to create persistent instances or read and update their attributes.

Option B reverses the platform ' s metadata-driven architecture: application JavaScript does not define a new custom-object schema. Option C is also premature because runtime handling logic cannot reliably use an object type that has not yet been established.

In a managed implementation, the definition should normally be created on staging and replicated as Object Definitions rather than manually recreated in production.

Study Guide reference:Data Management Using Business Manager Usage — Custom Object Types, object definitions, attributes, storage scope, replication, and CustomObjectMgr.

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