What can the seller do during an auction with reserve?

The correct answer highlights that during an auction with reserve, the seller has the ability to reject or confirm a bid. This option underscores the nature of reserved auctions where the seller sets a minimum price that must be met for the item to be sold. If bids do not reach that threshold, the seller is not obligated to complete the sale, allowing them the discretion to either accept a bid that meets or exceeds their reserve or decline any bids that fall short.

In an auction with reserve, the seller retains control over the sale process, which can include decisions on individual bids and the overall outcome based on their established reserve price. This flexibility is an important component of auctions with reserve, as it embodies the seller’s right to ensure their interests are protected.

The other options do not accurately describe the seller's role in a reserve auction. For instance, confirming the sale at any time during the auction would not be applicable, as the seller can only finalize the sale if the reserve is met. Bidding anonymously generally pertains to bidders rather than the seller's rights. The restriction on withdrawing from the auction only once is misleading since sellers can withdraw the item at any time as long as they haven't agreed to the sale, provided no binding auction laws or agreements prohibit it.