Explanation: Survival craft portable VHF radios are designed for critical voice communication in emergency situations. Statement C is incorrect because Channel 70 is exclusively designated for Digital Selective Calling (DSC), which is a digital signaling system, not for simplex voice communication. These portable survival radios operate simplex on Channel 16 (the international distress, safety, and calling frequency) and other voice working channels. The other statements are true requirements: A) These radios must be watertight to ensure functionality after immersion. B) A minimum effective radiated power of 0.25 watts ensures a usable signal range. D) A fixed, non-removable antenna prevents loss or damage in an emergency.