19. Consider a uniform metal bar with both ends in contact with thermal reservoirs, one at a fixed high temperature (Th) and the other at a fixed low temperature (Tc). After reaching thermal equilibrium, which of the following statements is false? (A) The temperature gradient is a constant across the metal bar. (B) The change in entropy of the high-temperature reservoir is negative. (C) If the length of the metal bar increases, the heat flux does not change. (D) The heat flux is uniform throughout the metal bar. (E) None of the above is false.