单次点击成本 (CPC) 最低的推广活动总是能实现最高投资回报率。

False. While a low Cost Per Click (CPC) can be beneficial, it doesn't automatically guarantee the highest Return on Investment (ROI). ROI is calculated based on the revenue generated relative to the cost. A campaign with a slightly higher CPC might attract more qualified leads or customers who spend more, leading to significantly higher revenue and thus a better overall ROI. Conversely, a very low CPC might bring in a large volume of clicks from less interested users, resulting in minimal conversions and a poor ROI despite the low cost per click. Therefore, optimizing for ROI requires considering both cost and conversion value, not just the lowest CPC.