A student is preparing a synthesis essay. Proposed thesis: Public libraries should be funded as digital access centers because they connect technology, instruction, and trusted public space. Source options: Source 1: A budget and outcomes report from a public agency that connects spending, usage, and access measures for public libraries and digital access. Source 2: A classroom or neighborhood anecdote about public libraries and digital access that is vivid but too narrow to establish a general pattern. Source 3: An academic literature review that synthesizes several studies about public libraries and digital access and separates strong findings from uncertain claims. Source 4: A promotional page from a vendor or advocacy group that would benefit from spending on public libraries and digital access; it highlights advantages and omits limitations. Source 5: An interview with a practitioner who works directly with public libraries and digital access and explains practical conditions that would make the thesis plausible. Source 6: A credible opposition brief on public libraries and digital access that uses data to raise a limitation, helping a writer qualify the argument responsibly. Source 7: A local implementation narrative showing how leaders adapted a public libraries and digital access policy when the first plan produced unintended barriers. Source 8: A poll of followers of a social media account devoted to public libraries and digital access; it reports percentages but gives no sampling method or comparison group. Which combination of sources would provide the most relevant, credible, varied, and sufficient support for this thesis?