Step 1: In a 'coming together' federation independent States come together on their own to form a bigger unit, pooling sovereignty while retaining their identity, so as to increase their security. Step 2: The USA, Switzerland and Australia belong to this category; in them all the constituent States usually have equal powers and are strong vis-a-vis the federal government. Step 3: India, Spain and Belgium are examples of the 'holding together' type, in which a large country decides to divide its power between the constituent States and the national government, and the central government tends to be more powerful. Step 4: Hence the coming together federation among the given options is Australia - Option (D).