Which statement describes a situation where convection is least likely to occur?
a. Heat travels from hot coffee to a metal spoon that is used to stir the coffee.
b. Heat travels from the warm top layer of a lake to the cooler depths of the lake.
c. Heat travels from the hot liquid layer of the Earth's core to the cooler liquid
beneath the crust.
d. Heat travels from the warmer water to the cooler air above the water.