The correct answer is A. Create a lookup relationship on Asset Inventory to Asset. Add the Asset Inventory related list to the Asset page layout.

To show Asset Inventory records as a related list on Asset, the child object must contain the relationship field pointing to the parent object. In this scenario, Asset Inventory is the child/detail-style object, and Asset is the parent record where the related list should appear.

Salesforce relationship fields connect records between objects, and related lists can then be added to the parent object’s page layout. Salesforce documentation for related lists confirms that related lists are managed from the object’s page layout.

Why others are incorrect:

B is incorrect because a roll-up field does not create the relationship or related list.

C is incorrect because the relationship direction is wrong; the relationship field should be created on Asset Inventory, not on Asset.

D is incorrect because a junction object is only needed for many-to-many relationships. Here, Asset Inventory records simply need to relate to Asset records.

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