Which morpheme means 'to slide'?

• A. Lapse
• B. Lux(o)
• C. Lumph(o)
• D. Lith(o)

Answer: (A)

The main idea is recognizing morphemes that convey specific meanings. The root meaning “to slide” comes from Latin labi, tied to slipping or slipping by. The morpheme laps(e) is built from that idea and shows up in words like lapse or elapse, where the sense is something slipping or sliding by. That makes it the correct pick for “to slide.” The other options point to completely different concepts: lux(o) relates to light, as in luminous or illumination; lith(o) comes from Greek lithos meaning stone. The form that looks like it might relate to lymph or lymphatic tissue isn’t tied to sliding. So the lapse morpheme best fits the meaning “to slide.”