Question

En el futuro, los teléfonos quizás cambiarán a ser más pequeños. (1 point)

Answer 1

“In the future”

So is the first one, “habrán cambiado”.

Explanation:
If you put the 3rd one is wrong because is talking in the present form, like now and not something that is going to happen in the future and that is not what the sentence is stating.