True or false? If an advertiser's goal is sales efficiency, they should decrease bids on keywords with high ACOS.

True. If an advertiser's goal is sales efficiency, decreasing bids on keywords with high ACOS (Advertising Cost of Sales) is a sound strategy. High ACOS indicates that the advertising spend on those keywords is generating proportionally lower sales, making them less efficient. By reducing bids, the advertiser can lower the cost per click and potentially improve the ACOS for those keywords, thereby increasing overall sales efficiency. Conversely, increasing bids on high ACOS keywords would further reduce efficiency, and maintaining bids would not address the inefficiency.