Why do underwater objects appear distorted when you see them from above?
reflection
refraction
diffusion
diffused reflection
specular reflection

The correct answer to the question is : Refraction.

EXPLANATION:

Before going to answer this question, first we have to understand refraction.

Refraction is the optical phenomenon in which light rays are bent at the interface of the two media due to their optical density difference.

When light comes from optical rarer medium to optical denser medium, the rays are bent towards the normal at the point of incidence.

Similarly light rays bend away from the normal when they pass from optical denser medium to optical rarer medium.

As per the questions, the object is present inside the water.  The water is optically denser as compared to air. Hence, the light coming from the object is bent at the air-water interface due to refraction of light. That's why the  object is appeared to be bent.

Hence, the correct answer is refraction.

diagram is missing, but i will try to explain your doubt.

answer:

amplitude is the maximum displacement or distance moved on a point of a vibrating body or wave measured from its equilibrium position.it is equal to half the length of vibration path.