An Account Strategist regularly reviews their company’s optimization score

By comparing the company’s current sales to the company’s historic sales data
By comparing the company’s website to the websites of the company’s competitors
Based on campaign aspects such as campaign statistics, settings, and industry trends
By analyzing the popularity of the company’s ads on social media

An Account Strategist regularly reviews their company’s optimization score in order to make sure that their Google Search campaign is as effective as possible. How is this optimization score calculated?