Combining form meaning chest or chest wall?

• A. Thorac/o
• B. Histo/o
• C. Glyc/o
• D. Lith/o

Answer: (A)

The main idea is recognizing which combining form names the chest. Thorac/o is the combining form that means chest or thorax, the region enclosing the heart and lungs. It’s used to form terms related to the chest, such as thoracotomy (surgical opening into the chest) or thoracic (pertaining to the chest). The other options don’t refer to the chest: histo/o means tissue, glyc/o means sugar, and lith/o means stone. So thorac/o is the correct choice for chest or chest wall.