Which type of order would not be adjusted on the ex-dividend date?

The correct answer is that a buy stop order would not be adjusted on the ex-dividend date. A buy stop order is an order to purchase a security when its price rises to a specified level, which is typically above the current market price. This type of order is primarily concerned with price movement and not directly related to dividend payments.

On the ex-dividend date, stock prices typically drop by the amount of the dividend to reflect that new buyers will not receive the upcoming dividend. However, since a buy stop order is based on price rather than the specifics of dividend payments, it remains unchanged regardless of the stock's dividend status.

In contrast, other types of orders, such as buy limit orders or sell stop orders, may be affected by the stock's price change due to the ex-dividend adjustment. Therefore, recognizing that a buy stop order’s main function is tied to price, rather than dividends, clarifies why it does not undergo adjustments on the ex-dividend date.