Which of the following describes the realists' problem of relative gains? a. A situation where both sides may gain, which would lead to a mutual increase in state power b. A situation where both sides are negatively affected by trade and in a position to lose power c. A situation where the efficiency of trade benefits becomes more important than the distribution of benefits d. A situation where, even if both sides gain, the side that gains more may increase its power over the side that gains less