Activation energy is defined as the minimum amount of energy required for activating the atoms or molecules to undergo chemical transportation or transfer.
The correct answer is:
Option D. The letter A.
In the graph, activation energy can be explained as:
1. The activation energy is the minimal amount of energy necessary for the compounds to participate in the chemical reaction.
2. In the graph, the activation energy without the enzyme is represented by A, the activation of energy with enzyme is represented by B, and the change in the free energy is represented by C.
Thus, the correct answer is Option D.
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