The correct answer is C) particular average. In the context of marine insurance, particular average refers to a partial loss or damage to the insured cargo, which in this case is the 20 bales of cotton that were damaged by the fire. This is different from a general average, which involves the intentional sacrifice of part of the cargo to save the whole ship and remaining cargo. It is also not a total loss of a part or a constructive total loss, which would involve the entire cargo or the ship itself being lost or destroyed. The key is that the damage is limited to a portion of the cargo, rather than the entire cargo or the ship, making this a particular average claim under marine insurance policies.