The answer is already in the blank for, its was greater
B) Copper atoms have a loosely held free electron in their outer shell that is able to move freely to other atoms.
This phenomenon is as a result of static friction created by the tumbling clothes. Static friction results from the rubbing together of two or mores objects or body and electrons are stripped from one surface of the clothes more than the other. This creates an electrostatic force of attractions between the positive charges on one cloth and the negative charges on the other cloth.(unlike charges attract).
If I am not wrong i thinks it is in the toroid uniforms