Rate of reaction — practice question

The energy profile diagram for a chemical reaction is shown. What is the activation energy of the reaction?

• A$-200\,\text{kJ mol}^{-1}$
• B$-100\,\text{kJ mol}^{-1}$
• C$+100\,\text{kJ mol}^{-1}$
• D$+200\,\text{kJ mol}^{-1}$