Una escalera de 6 pies esta apoyada a
una pared. La distancia entre la pared y la base
de la escalera es 4 pies. A qué altura se
encuentra la parte superior de la escalera
del piso?

3) AC=AC

Step-by-step explanation:

The third answer is correct because it is the only answer that shows the reflexive property in the triangle. The reflexive property of congruency states that any shape is congruent to itself. So this proves that the line AC must be congruent to itself. The second answer also shows a line congruent to itself, however, D is not shown on the image, therefore the line does not exist; additionally, that information would not prove the 4th statement in the proof.