Antonio has a line-item that is under-delivering. Which of the following manual optimization tactics should he consider? (Select 2)

When a line item is under-delivering, the goal is to increase impression opportunities. Relaxing the viewability setting makes more inventory available, as it lowers the threshold for what is considered viewable, thus increasing potential impressions. Selecting any unchecked supply sources also expands the available inventory by allowing the line item to bid on impressions from previously excluded sources. Decreasing bids would further reduce delivery by making the line item less competitive. Decreasing frequency caps would allow users to see the ad more often, which might increase impressions per user, but it doesn't address the fundamental issue of limited reach or available inventory for the line item to bid on.