What capability is common among all surface combatants?

All surface combatants in the U.S. Navy share the common capability of having heavy armament for engaging in sea battles. This is a fundamental characteristic that enables these vessels to perform their primary role, which is to combat enemy naval forces and protect maritime interests. The armament installed on surface combatants can vary, but generally includes a combination of guns, missiles, and sometimes torpedoes, all designed to deliver effective firepower during naval engagements.

While other options describe capabilities that may be found in some surface combatants, they do not apply universally across all classes. Engagement of enemy forces on land can occur, but it's not a primary function for every surface combatant, since some are focused more on anti-air and anti-submarine warfare. Mine warfare operations are specific to certain vessels that specialize in mine countermeasures, not a common trait among all. Conducting underwater research typically belongs to submarines or specific research crafts, rather than surface combatants. Therefore, the heavy armament for sea battles truly represents a defining feature common to all surface combatants within the Navy.