The correct response is:
a Before the layers touch, the outer layer is hotter than the inner layer. Once the layers are touching, the outer layer will transfer kinetic energy to the molecules in the cooler inner layer until both layers reach the same temperature, which will be in between their starting temperatures.
This response accurately describes the thermal interaction between the two layers, where heat transfer occurs from the hotter outer layer to the cooler inner layer, resulting in both layers eventually reaching thermal equilibrium at a temperature that is between their initial temperatures.