Which prefix indicates relationship to life?

• A. andr/o
• B. pulmon/o
• C. phot/o
• D. bi/o

Answer: (D)

Life-related concepts are conveyed by the combining form bio- (bi/o). This element signals living things or life itself, as seen in biology (study of life), biopsy (viewing living tissue), and biomarker. The other options tie to different ideas: andr/o refers to male/man, pulmon/o to the lungs, and phot/o to light. So bio-/bi/o is the one that indicates relationship to life.