What is the cooling water used in moderator heat exchanger during normal operation? And during class IV failure?

What is the cooling water used in moderator heat exchanger during normal operation? And during class IV failure?
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During normal operation process LP water is used in moderator heat exchangers, which transfers heat to seawater. During class IV failure firewater is used for the moderator heat exchanger. 
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Last Answer : (D) All (A), (B) and (C)

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