B is the correct answer. Other options may look alike. However for a state to be recognized it must have the attributes in option B. For instance, option A only explained the presence of a government, police, army, navy and air force but no population, sovereignty, and territory. So that’s incomplete. Option C only explain two tiers of government. These are not enough adjectives to describe a state. Option D is equally wrong because: It had no government, sovereignty, population and territory.