R, S and T are points with RT = 2RS. Which of the following could be true? I. R, S and T are the vertices of a right triangle. II. R, S and T are three of the vertices of a square. III. R, S and T all lie on the circumference of a circle.
(A)I only (B)III only (C)I and II only (D)I and III only (E)I, II, and III
D