The U.S. Coast Guard communications station providing HF MSI (Maritime Safety Information) broadcast coverage for NAVAREA XII is:

Correct Answer: Option C — NMO (Honolulu)

USCG station NMO, located in Honolulu, is responsible for the HF MSI broadcasts for NAVAREA XII. This area encompasses the Pacific Ocean north of the equator and east of the International Date Line. Mariners must monitor these specific frequencies to maintain compliance with GMDSS watchkeeping and safety information requirements.