Which combining form means 'starch'?

• A. Lact/o
• B. Lei/o
• C. Caud/o
• D. Amyl/o

Answer: (D)

Combining forms carry the meaning of the substance they refer to, and this item is asking which form names starch. The form that means starch is amyl/o, from Greek amylon. It shows up in terms like amylase, the enzyme that digests starch, and amylose, a component of starch. The other options point to different things: lact/o means milk, lei/o means smooth (as in smooth muscle terms), and caud/o means tail. So amyl/o is the correct combining form for starch.