The characteristics of two methods of heat transfer are listed below: Method A: No material medium is required and heat is transferred in all directions Method B: Material medium like gas or liquid is required and heat is transferred only in the vertically upward direction Which statement is correct? Method A is radiation and Method B is conduction. Method A is radiation and Method B is convection. Method A is conduction and Method B is radiation. Method A is convection and Method B is radiation.