In an auction with reserve, what happens after the auctioneer announces the completion of the sale?

In an auction with reserve, once the auctioneer announces the completion of the sale, the seller indeed loses the right to reject bids. This means that the auctioneer has indicated that the final bid has met the reserve price set by the seller. By declaring the auction complete, it creates a binding agreement between the highest bidder and the seller, leading to an obligation to complete the sale.

This is a key aspect of auctions with reserves, as it provides clarity for both parties involved. The seller has the protection of not having to sell the item unless the bids meet their expectations, but once the auction concludes with a valid bid at or above the reserve, they are committed to selling the item.

The other options do not accurately reflect the rules governing a reserve auction. For example, the seller does not have the option to withdraw items after the auction has officially concluded, and bid prices cannot be adjusted once the sale is complete. Similarly, reopening the bidding for higher offers contradicts the finality of the auction's outcome as established by the auctioneer's announcement.