Which of these is not an example of physical weathering? Freeze-thaw

Acid rain falling on limestone

Wind blowing sand onto a rock

b. is the answer hoped i        

if the temperature drops and becomes cool

then the atmosphere can be freezing as the water vapor in the air is at maximum (100%) and can be severely cold

also can be snowing lightly as the moisture in the air will start to solidify

and btw this is not chemistry but