Which of the following is NOT in the microwave frequency range?

The Very Low Frequency (VLF) range is characterized by its lower frequencies, typically between 3 kHz and 30 kHz, which falls far below the microwave frequency range. The microwave frequency range generally includes frequencies from approximately 300 MHz (0.3 GHz) to 300 GHz.

In contrast, the Ultra High Frequency (UHF), Super High Frequency (SHF), and Extremely High Frequency (EHF) ranges are all located within or overlapping with the microwave frequencies. UHF spans from 300 MHz to 3 GHz, SHF extends from 3 GHz to 30 GHz, and EHF covers frequencies from 30 GHz up to 300 GHz. This context helps clarify why VLF, with its significantly lower frequency, is not considered part of the microwave frequency range, differentiating it from the other options provided.