Which of the following would you analyze using the "Audience" report in Google Analytics?

Analyzing the demographic details of users visiting the site is a primary function of the "Audience" report in Google Analytics. This report provides insights into various characteristics of the website's visitors, including age, gender, interests, geographical location, and language. Understanding these demographic details is crucial for businesses and marketers as it helps them tailor their content and marketing strategies to better suit their audience's preferences and behaviors.

The other options pertain to different areas of analysis within Google Analytics. For instance, the source of website traffic would be addressed in the "Acquisition" reports, which help identify where visitors are coming from, such as search engines, social media, or referral links. The bounce rate is typically analyzed within the "Behavior" reports, offering insights on user engagement and how well the content is retaining visitors. Lastly, the performance of ads would be monitored in the "Acquisition" section, particularly in reports that focus on campaigns and traffic driven by advertisements. Thus, while all options are relevant to website analysis, the demographic details fall squarely within the scope of the "Audience" report.