On a summer afternoon, the sand on the beach can get very hot. When you step on the sand in bare feet, you can burn yourself.

Which of the following sentences best describes how this happens?
Heat from the Sun is transferred to the sand without direct contact. This heat is then transferred to your feet without direct contact.

Heat from the Sun is transferred to the sand without direct contact. This heat is then transferred to your feet by direct contact.

Heat from the Sun is transferred to the sand by direct contact. This heat is then transferred to your feet by direct contact.

Heat from the Sun is transferred to the sand by direct contact. This heat is then transferred to your feet without direct contact.