A Stirling cycle and a Carnot cycle operating between 50 C and 350 C. Their efficiencies are ηs and ηc respectively. In this case, which of the following statements is true?
A. ηs > ηc
B. ηs = ηc
C. ηs < ηc D. The sign of (ηs - ηc) depends on the working fluid used