Which of the following transmissions is permitted for all amateur stations?
Unidentified transmissions of less than 10 seconds duration for test purposes only
Automatic retransmission of other amateur signals by any amateur station
Occasional retransmission of weather and propagation forecast information from US government stations✓Bonne réponse
Encrypted messages, if not intended to facilitate a criminal act
Explication
Retransmitting non-amateur signals is generally prohibited, but the rule carves out propagation and weather forecast information from US Government stations, provided it stays occasional. The other choices describe unidentified transmissions, blanket automatic retransmission and encryption, all of which Part 97 forbids.