One end of a metal rod is kept in a furnace. In steady state, the temperature of the rod.

In steady state, the temperature at any point of the material remains unchanged as time passes. Hence the end near the furnace will be extremely hot whereas the other end will have minimum temperature. Thus, showcasing nonuniformity in the temperature throughout the metal rod.
In steady state there is no change in temperature hence first two options are not valid.
The temperature us not constant throughout the rod, it’s different at different points. Hence third option is incorrect too.
Thus option (d) is the correct option.