The correct answer is A.Consequences of the Peace of Westphalia may be summarized as follows:

• First, the peace treaties were negotiated and signed by the states dominated by the rulers that were commonly accepted as sovereigns of their realms.

• Second, the physical borders of each state were recognized and commonly accepted. Therefore, each of these units represented a political entity.

• Third, each sovereign who represented a state was accepted as equal, regardless of the size of lands they ruled or the nobility o which they belonged.

• Fourth, though no international organization emerged as a body until the late 19th century, the way in which these peace accords were made initialized a method that enabled states to communicate collectively through diplomatic instruments. Thus, it is possible to assert that the Peace of Westphalia laid the foundations of collective diplomacy and established the basis of the Congress System that would help institutionalize the international environment in the following centuries.