Answer:
c) required for a chemical reaction to begin.
Explanation:
Activation energy is the minimum amount of energy required to initiate a chemical/bio-chemical reaction. Most of the reactions are slow because they require a lot of energy to get initiated. So in order to initiate reaction, enzymes provide an alternate pathway which requires comparatively less amount of energy. Substrate of a reaction binds to the enzyme which results in change of shape of the substrate in such a manner that ultimately causes activation energy to get lowered. In short we can say that enzyme holds the substrate in such a manner that requires less activation energy and hence increases the catalysis.
