If Carnot cycle has maximum possible thermal efficiency, then why don’t the steam turbine power plants run on Carnot cycle?

• A. Because the process of heat addition is at constant temperature
• B. As mean temperature of heat addition is quite low in case of Carnot cycle
• C. Since work consumed by compressor is approximately equal to work produced by turbine
• D. Because boiler can’t be maintained at constant pressure in Carnot cycle