For a Performance Max campaign targeting omnichannel goals, it’s best to segment products by their performance and respective business objectives.

• Segment products by availability and product type
• Include all products from the local product inventory feed
• Include all products from the local product feed
• Segment products by performance and business goals

The correct answer is: Segment products by performance and business goals

Explanation: When employing Performance Max, marketers have access to a suite of novel insights and reports. Tools at your disposal include Audience Signals, Product Listing Groups Reporting, and insights available via the Insights Page, not to mention Product Diagnosis. Amidst the various campaign structuring approaches, one stands out: the segmentation of products based on performance metrics and aligned business targets. This strategy ensures you harness the full potential of Performance Max in pursuit of omnichannel objectives.