Which best describes the shape of myoglobin which in many ways is a typical protein?

By definition, myoglobin is a specific protein enzyme that is found in the muscular cells of humans and animals wherein it functions as a carrier of oxygen to be supplied to these cells. In addition, the shape of these enzymes are usually with respect to its iron and oxygen bondings.

Ithink that b is correct but just in case wait to see if someone else answers