Valid Java Constructor Calls

Consider the following Student class declaration.

public class Student  
{
  private String myName; 
  private int myAge; 
   
  public Student() 
  {  /* implementation not shown */  } 

  public Student(String name, int age) 
  {  /* implementation not shown */  } 

  // No other constructors 
}

Which of the following variable declarations will compile without error?

I. Student a = new Student();

II. Student b = new Student("Juan", 15);

III. Student c = new Student("Juan", "15");