T9B12:What is standing wave ratio (SWR)?
Direct answer summary (2026-2030 NCVEC pool)
The official correct answer for T9B12 is A measure of how well a load is matched to a transmission line.
The key fact is A measure of how well a load is matched to a transmission line. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.