Explanation: Days: Sat, Sun, Mon (P), Tue, Wed (S), Thu. Remaining days: Sat, Sun, Tue, Thu. Remaining patients: M, N, Q, R. M must be before R. Q must be immediately before/after N. Possible (Q, N) or (N, Q) slots: (Sat, Sun), (Sun, Sat), (Tue, Thu), (Thu, Tue) - (No, Tue and Thu are not adjacent). (Tue, N/A), (Thu, N/A). QN/NQ must be Sat/Sun or Sun/Sat. Case 1: Q=Sat, N=Sun. Schedule: Q, N, P, _, S, _. Remaining days: Tue, Thu. Remaining patients: M, R. M must be before R. M=Tue, R=Thu. Full: Q, N, P, M, S, R. In this case, Ratul (Thu) is later than Shimul (Wed). Case 2: N=Sat, Q=Sun. Schedule: N, Q, P, _, S, _. Remaining days: Tue, Thu. Remaining patients: M, R. M must be before R. M=Tue, R=Thu. Full: N, Q, P, M, S, R. In this case, Ratul (Thu) is later than Shimul (Wed). Option C: Ratul must be treated later in the week than Shimul. Shimul is Wed. Ratul is Thu in both acceptable cases. Therefore, C is true.