A HIWAS broadcast can be received if the NAVAID has what feature?

The correct answer pertains to the specific visual indication used in aeronautical charts to denote various features of navigational aids. A HIWAS broadcast, or Hazardous Inflight Weather Advisory Service, is indicated by a blue filled-in circle with a white letter "H" next to the NAVAID on aeronautical charts. This symbol signifies that the NAVAID is equipped to provide a HIWAS broadcast which is critical for pilots to receive timely weather information while in flight.

The features provided in the other options do not specifically relate to HIWAS capability. For instance, a frequency written above the box is a standard notation on charts but does not indicate HIWAS functionality. Similarly, the asterisk preceding a NAVAID frequency may denote different types of information or services but does not indicate the presence of a HIWAS broadcast. The red triangle with an 'X' is typically used to mark the location of VORs or other navigational aids but does not convey information regarding weather advisory services. Thus, recognizing the blue filled-in circle with a white "H" is essential for pilots and air traffic controllers identifying NAVAIDs capable of transmitting HIWAS broadcasts.