The correct option is B.
Leather shoes are made form leather, which is a natural polymer. Leather is usually obtained by tanning the hides of animals, especially cattle. Natural polymers refer to those polymers that are obtained naturally from nature. Examples are wool, silk, leather, keratin, etc. Synthetic polymers on the other hand are man made, they are produced by combination of chemical substances in the industries. Examples are plastics, polyethylene, nylon, etc.