Every time that your ad is eligible to show, AdWords calculates its Ad Rank using your bid amount, components of Quality Score and

Every time that your ad is eligible to show, AdWords calculates its Ad Rank using your bid amount, components of Quality Score 

• the daily budget you’ve set
• your historical conversion rate
• the expected impact of extensions and other ad formats
• the search ranking of your website

Correct answer is:

• the expected impact of extensions and other ad formats