Question

2 conduction can only occur between two objects when—
a one object is less dense than the other.
b one of the objects is made of metal.
c both objects are exactly the same temperature.
d both objects are in physical contact with each other.

Explanation:

Conduction is heat transfer through direct physical contact between objects. Density, metal composition, or equal temperature are not required for conduction to occur: density does not affect conduction possibility, non-metal objects can conduct heat (e.g., wood), and heat stops transferring when temperatures are equal. Direct contact is the essential requirement.

Answer:

D. both objects are in physical contact with each other.