G2B06 (A) 
What is a practical way to avoid harmful interference when selecting a frequency to call CQ on CW or phone?
A. Send "QRL?" on CW, followed by your call sign; or, if using phone, ask if the frequency is in use, followed by your call sign
B. Listen for 2 minutes before calling CQ 
C. Send the letter "V" in Morse code several times and listen for a response
D. Send "QSY" on CW or if using phone, announce "the frequency is in use", then send your call and listen for a response
