A day order is an order whose validity is restricted to the trading day on which it is entered. Unlike a good-till-cancelled order, which can remain available for execution across subsequent trading sessions until cancelled or otherwise terminated under applicable rules, a day order does not carry forward automatically. Consequently, if a DFM day order to sell remains unexecuted when the trading day ends, the order automatically expires . The investor does not receive a post-close choice simply to carry the same day order into the following session, and the broker does not possess discretion to convert an expired day order automatically into a continuing order. If the investor still wishes to sell the securities on the following trading day, a new valid order must be entered under the appropriate order-validity instruction. The distinction between day orders and longer-duration orders is important because it determines how long an instruction remains exposed to the market. Therefore, among the alternatives provided, automatic expiry at the end of the trading day accurately reflects the nature of a day order, making option C correct.

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