Awooden walkway and a sandy beach are at the same temperature. the sand feels much hotter because it has a greater

Specific heat capacity.

As it has a greater specific capacity than wood, it takes more heat energy to increase it's temperature by 1 degree Celsius than that of wood. Hence, though both are at the same temperature, sand contains way more heat than wood.  

Ibelieve that the correct answer is: c. along plate boundaries