The hypotenuse of right triangle ABC is AC, and the hypotenuse of right triangle DEF is DF. If points A, C, D, and F all lie on the same line, which of these statements is true about the two triangles? A. They need not be similar, and they need not be congruent.
B. They must be similar, but they need not be congruent.
C. They must be congruent, but they need not be similar.
D. They must be both similar and congruent.