Marina Exam Reviewer: When receiving station can not distinguished the signal what signal flag is to be hoisted?

Marina Exam Reviewer

When receiving station can not distinguished the signal what signal flag is to be hoisted? 

A. Keep Code pennant at the dip 
B. Hoist ZL 
C. Hoist ZQ 
D. Raise and lower the answering pennant 

Answer:      A. Keep Code pennant at the dip 

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