Final answer:
The greatest disadvantage of using sensor paste over gel or cream is that it can cause serious burns as it increases the energy transferred to the skin.
Step-by-step explanation:
The greatest disadvantage of using sensor paste over gel or cream is that it would result in much more energy being transferred to the skin, which can cause serious burns. This is because sensor paste increases the resistance, leading to an increase in power transferred to the skin based on the equation P = I² R. On the other hand, gel reduces the resistance, thereby reducing the power transferred to the skin.