A client who owns a fine-dining restaurant in London wants to get more phone calls from people researching places to eat on their mobile phones. How should you optimize this client’s campaign to help achieve their goal?

Include a phone number in the client’s ad’s headline and monitor performance with the top vs. other segment
Add call extensions to the client’s ads and monitor performance with the top vs. other segment
Add call extensions to the client’s ads and monitor performance with the mobile clicks-to-call segment
Include a phone number in the client’s ad’s headline and monitor performance with the mobile clicks-to-call segment

Explanation: Ads created in call-only campaigns are fine-tuned to show only on mobile devices that are capable of making calls. Read more here

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