Which of the following best describes the function of a galvanic isolator?

A galvanic isolator serves the primary function of preventing corrosion caused by stray DC currents in marine environments. In scenarios where two different metal types are electrically connected in the presence of an electrolyte, galvanic corrosion can occur. This is because electrons flow from one metal to another, leading to the deterioration of one of the metals, generally the less noble one.

By installing a galvanic isolator, the electrical connection is effectively broken for DC currents while allowing AC currents to pass through. This selective blocking protects the metallic components of vessels from galvanic corrosion without compromising the functionality of the AC power system. Thus, it plays a crucial role in extending the lifespan of metal structures and components in marine applications by mitigating the corrosion process.

The other answer choices do not accurately define the primary role of a galvanic isolator. Blocking AC current, balancing load between phases, or enhancing signal integrity do not relate to the prevention of corrosion from DC currents, which is the key function of a galvanic isolator.