Answer: d) Dutch auction
Explanation:
Dutch Auction refers to a type of Public Offering in which the issuing company holds a sort of auction and receives bids on the shares that it has in. Using these bids they are able to set a price for the stock which is the highest price received.
However, the bids are based on the amount an investor can buy in terms of quantity and price. The lowest acceptable bid is then charged on all the stock and is called the Uniform auction price which is what Blue Stone paid thereby making this a Dutch Auction.