Let's consider a classical ideal gas whose single-particle partition function of molecules is Z 1 . Which of the following statements is true? Select one: O a. If the gas molecules of N molecules cannot be separated from each other, and the partition function Z N of the system is written Z N = Z 1 , the entropy of the gas calculated from Z ~ is obtained , which is an extensive quantity. O b. If the molecules cannot be separated from each other, the partition function of the system can be written in the form ZN = ZIN /N !. In this case, the entropy calculated from Z N is obtained, which is an extensive quantity. O c. If the gas molecules of N molecules cannot be separated from each other, the partition function Z ~ of the system can be written Z N = ZIN