______ help advertisers benchmark against industry norms or conduct side-by-side comparisons to other media investments.

The correct answer is Third-party measurement because this type of measurement provides advertisers with objective insights and analytics that allow them to benchmark their performance against industry norms and conduct side-by-side comparisons with other media investments. Third-party measurement solutions aggregate data from various sources, offering a comprehensive perspective on how advertising efforts are performing in relation to competitors and industry standards. In contrast, first-party measurement focuses on data collected directly from an advertiser's own campaigns, and brand metrics typically evaluate specific indicators related to brand performance without providing broader comparative insights, making third-party measurement the most suitable choice for benchmarking and comparative analysis.