Areaction progress curve has three peaks and two valleys between the peaks. this curve describes a reaction mechanism that involves a. three elementary reactions b. one compound decomposing into three parts c. three compounds combining together d. two elementary reactions

            A reaction progress curve has three peaks and two valleys between the peaks. This curve describes a reaction mechanism that involves three elementary reactions.

Explanation:
                   I have drawn the progress curve with three peaks and two valleys. In fact the peaks shows higher energy and valleys show lower energies. So, Let suppose we react A and B. This reaction between A and B results in the formation of C. In this reaction the energies of A and B are less, and during the progress of reaction they cross a transition state of higher energy and forms product C with lower energy which is present at lower valley. This was first reaction. Other two reactions will be followed by conversion of C to D and conversion of D into E.