Which term means lengthening?

• A. Expand
• B. External
• C. Extension
• D. Fatigue

Answer: (C)

Lengthening is represented by extension. This noun names the act or result of making something longer—stretching it along its length or increasing its length. You can talk about the extension of a deadline, or the extension of a rod, or even a limb being extended in the sense of straightening along a length. Expand can mean to become larger in size or scope in a broader sense, not specifically about length, while external and fatigue do not denote length change.