Task: Question Answering
Input (English): Question: The triple point of a phase diagram of a component: 
 Options:  <1> Presents 3 degrees of freedom, according to the rule of the phases. <2> Presents 1 degree of freedom, according to the rule of the phases. <3> It is characterized because the liquid and gas phases are indistinguishable. <4> It is characterized because there are three phases in equilibrium. <5> It is characterized because there are four phases in equilibrium.
Output (English): 4