When heat is transferred from one body to another, the internal energy given up by the first body must be greater than the internal energy taken up by the second body.

When heat is transferred from one body to another, there is no mathematical relationship between the internal energy given up by the first body and the internal energy taken up by the second body.

When heat is transferred from one body to another, the internal energy given up by the first body must be less than the internal energy taken up by the second body.

When heat is transferred from one body to another, the internal energy given up by the first body must be equal to the internal energy taken up by the second body.