What is the most important reason why an icy moon is more likely to be geologically active than a rocky moon of the same size? what is the most important reason why an icy moon is more likely to be geologically active than a rocky moon of the same size? ice contains more radioactive elements than rock. ice is less rigid than rock. ice is affected by tidal forces to a greater extent than rock. ice is less dense than rock. ice has a lower melting point than rock.