To free the rock from atop the perch, you need a , which could take the form of a person or a lever to free the rock. a. workb. photonsc. kineticd. catalyste. potentialf. electromagnetic energyg. heat

Option (D)

Explanation:

In terms of chemistry, a catalyst is usually defined as the substance that is commonly used in a reaction in order to increase the rate of reaction, without getting consumed. It helps in the reduction of activation energy.

In the given case, the lever or a person can be considered as a catalyst because both of these will increase the efficiency (or rate) in removing the rock from the top of the perch. Thus, the lever or the human will remain the same after the removal of rock as a catalyst can be recovered after the reaction.

Therefore, the correct answer is option (D).

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.