The correct answer is D. All of the above.
Acid test is done to find out the weathering quality of stones. This is done by exposing the stone to a strong acid and measuring how much it is affected. Stones that are more resistant to acid will be more resistant to weathering.
Attrition test is done to find out the rate of wear of stones which are used in road construction. This is done by putting the stone in a machine that simulates the wear and tear that it would experience on a road. Stones that are more resistant to attrition will last longer on roads.
Crushing test is done to find out the compressive strength of the stone. This is done by putting the stone in a machine that squeezes it until it breaks. The amount of force required to break the stone is a measure of its compressive strength.
Stones that are resistant to acid, attrition, and crushing will be more durable and will last longer in a variety of applications.