Read this and answer the question

Externally, Orthodox Jews can be identified by their manner of dress and family lifestyle. Orthodox women dress modestly by keeping most of their skin covered. Additionally, married women cover their hair, most commonly in the form of a scarf, also in the form of hats, bandanas, berets, snoods or, sometimes, wigs. Orthodox men wear a skullcap known as a kipa and often fringes called "tzitzit". Haredi men often grow beards and always wear black hats and suits, indoors and outdoors. However, Modern Orthodox Jews are commonly indistinguishable in their dress from those around them.

what part of their body do married women cover with a scarf?
hair