如要判斷使用者透過哪個來源 (例如「自然搜尋」或「參照連結網址」等) 前往你的網站，應該使用什麼維度？

The correct answer is "應該使用工作階段主要管道群組 (預設管道群組)" (Should use Session primary channel group (Default Channel Group)). The Default Channel Group in Google Analytics categorizes traffic sources into high-level, predefined groupings like "Organic Search," "Direct," "Referral," and "Paid Search," which directly answers the question of identifying how users arrived at your site. "應該使用工作階段來源/媒介" (Should use Session source/medium) is too granular; while it provides the specific source (e.g., google) and medium (e.g., organic), the question asks for the type of source (e.g., "natural search" or "referral link"), which the channel group provides more directly. "應該使用 Google Ads 廣告活動" (Should use Google Ads campaign) is specific to paid campaigns and wouldn't capture all traffic sources. "應該使用網頁標題與畫面類別" (Should use Page title and screen class) describes content viewed, not how users arrived.