When ABC stock is trading at $ $40\mathrm{.}50,$ an equity trader places an order to buy $500,000$ shares of the stock at $3$:$58$ PM ET $,$ filled at $ $40\mathrm{.}60,$ and places another order to buy $400,000$ shares at $3$:$59$ PM filled at $ $40\mathrm{.}90.$ Because of these actions $,$ the stock closes at $ $41.$ The equity trader then uses those purchased shares to fill Market $-$ On $-$ Close orders to buy that the firm was holding for clients $.$ This is an example of : A Insider trading B Front running Marking the close D Painting the tape