Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric coaxial cable, assuming all other parameters are the same?

Foam dielectric coaxial cables inject air or an inert gas into the plastic insulation surrounding the center conductor. Because air is closer to a vacuum than solid plastic, it reduces the overall dielectric constant. This allows the RF waves to travel faster through the cable, meaning foam dielectric has a higher velocity factor. Air also introduces less RF absorption than solid plastic, which means foam dielectric cable has lower attenuation (lower loss) per unit of length. This makes it highly desirable for VHF, UHF, and microwave applications. However, replacing solid plastic with foam introduces a trade-off: air has a lower dielectric breakdown strength than solid polyethylene or Teflon. As a result, foam dielectric cables cannot withstand as high a voltage before arcing, giving them a lower safe maximum operating voltage. Since all three individual statements are correct, 'All these choices are correct' is the right answer.