In substitution type of questions, some particular objects are assigned code names. Then a question is asked that is to be answered in the code language.
If clock is called television, television is called radio, radio is called oven, oven is called grinder and grinder is called iron, in what will a lady bake ?
The lady shall bake in an 'oven' but 'oven' is called 'grinder'.
So, the lady will bake in a 'grinder'.