Which herb has bark as the part used and shows antimicrobial, antioxidant, and antispasmodic actions?

• A. Convallaria majalis
• B. Cordyceps sinensis
• C. Corydalis ambigua
• D. Cinnamomum zeylanicum

Answer: (D)

Recognize that the herb described is cinnamon, whose bark is the part used and which shows antimicrobial, antioxidant, and antispasmodic actions. Cinnamon bark carries essential oil rich in cinnamaldehyde, contributing strong antimicrobial effects against bacteria and fungi, and its polyphenolic constituents provide notable antioxidant activity. In addition, it has demonstrated antispasmodic effects on gastrointestinal smooth muscle, helping relax cramps and spasms. The other herbs listed do not use bark as the part employed, nor are their primary actions aligned with this combination of antimicrobial, antioxidant, and antispasmodic effects.