Answer : Option A) The iron is warmer than the shirt.
Explanation :
In the given information, the thermal energy in a hot iron flows into a shirt because the iron is warmer than the shirt. Usually the energy transformation takes place between the objects which are occupied with unequally distributed energy. Here, iron has higher thermal energy than the shirt that is suppose to be ironed. And shirt is having low thermal energy compared to iron. Therefore the energy flows from higher side to the lower one.