Which of the following is the correct definition of condenser efficiency?

• A. It is the ratio of the difference between the outlet and the inlet temperatures of cooling water to the difference between the temperature corresponding to the vacuum in the condenser and inlet temperature of cooling water
• B. It is the ratio of the difference between the temperature corresponding to the vacuum in the condenser and inlet temperature of cooling water to the difference between the inlet and outlet temperature of cooling water
• C. It is the ratio of the difference between the atmospheric pressure and the absolute pressure inside the condenser to the difference between the atmospheric pressure and the absolute partial pressure of the steam
• D. It is the ratio of the difference between the actual pressure inside the condenser and the partial pressure of the steam to the atmospheric pressure