The correct option is C Roots
Atropa belladonna is commonly known as belladonna or deadly nightshade. It is a perennial herbaceous plant in the family Solanaceae, native to Europe, North Africa, Western Asia, and some parts of Canada and the United States. The foliage and berries are extremely toxic, containing tropane alkaloids. Belladonna has been used in herbal medicine for centuries as a pain reliever, muscle relaxer and anti-inflammatory and to treat menstrual problems, peptic ulcer disease, histaminic reaction and motion sickness. The alkaloid 'belladonna' is obtained from roots and roots are used as sedative stimulant and antispasmodic. Thus, option B is correct.