General exam question G3C01
Subelement G3, RADIO WAVE PROPAGATION· Group G3C
G3C01
Which ionospheric region is closest to the surface of Earth?
- A.The D region (correct answer)
- B.The E region
- C.The F1 region
- D.The F2 region
WhyThe D region is the ionospheric region closest to the surface of Earth. The D region sits lowest in the ionosphere, closest to Earth's surface, and it's mainly responsible for daytime absorption on the lower HF bands rather than for refracting signals back down, answer A. The E, F1, and F2 regions all sit progressively higher.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2023-2027 NCVEC Element 3 pool (public domain); the explanation above is original writing, see our methodology.
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