A research analyst has changed his recommendation on a company from "buy" to "sell". The analyst faxed this change in investment advice to all his customers. Two hours later, one of his clients called in with a buy order for 500 shares of this company. Under these circumstances, the analyst:

should accept the order because it is a transaction specifically requested by his client.

should advise the customer of the change in recommendation before accepting the order.

should not accept the order until one day has elapsed after the communication of the change in recommendation.