Final answer:
NAVMACS II is a communications system used by the U.S. Navy for delivering text messaging services to its sea-based platforms.
Step-by-step explanation:
The Naval Modular Automated Communications System II (NAVMACS II) primarily delivers c) Text Messaging services. This system is utilized by the sea-based platforms of the United States Navy to provide rapid, reliable, and secure communications. It is not meant for video conferencing, voice communications, or satellite broadcasting, but it excels in handling text-based messages, including emails and official Navy traffic, over satellite links. The NAVMACS II system ensures efficient distribution of target data, tactical updates, and other mission-critical information across the fleet.