Metal Lids on Glass Jars Can Often Be Loosened by Running

Metal lids on glass jars can often be loosened by running them under hot water.Why is this?

A) The hot water is a lubricant.
B) The metal and glass expand due to the heating,and the glass being of smaller radius expands less than the metal.
C) The metal has a higher coefficient of thermal expansion than glass so the metal expands more than the glass thus loosening the connection.
D) This is just folklore.