Concept:OPEC focuses on coordinating petroleum policies among member nations.Explanation:OPEC stands for the Organisation of Petroleum Exporting Countries.A principal objective is to harmonise and align the oil policies of member countries.This coordination helps stabilise oil markets and secure fair prices for producers.Although OPEC influences international oil prices, direct price setting is not its main stated objective.Its main focus is mutual cooperation and policy alignment among members.Answer:Option B. Harmonise the oil policies of member countries.