Question ID:PT52 S2 Q5 Passage:Workers at a water treatment plant open eight valves‚ G, H, I, K, L, N, O, and P‚ to flush out a system of pipes that needs emergency repairs. To maximize safety and efficiency, each valve is opened exactly once, and no two valves are opened at the same time. The valves are opened in accordance with the following conditions:Both K and P are opened before H.O is opened before L but after H.L is opened after G.N is opened before H.I is opened after K. Stem:Which one of the following must be true? Correct Answer Choice:EChoice A:At least one valve is opened before P is opened. Choice B:At least two valves are opened before G is opened. Choice C:No more than two valves are opened after O is opened. Choice D:No more than three valves are opened after H is opened. Choice E:No more than four valves are opened before N is opened.