Question

which of these protected areas are most closely associated with areas that involve water all or part of the time?
national historic sites
national grasslands
national mountain areas
national wetland areas

Explanation:

Wetlands are areas where water covers the soil, or is present either at or near the surface of the soil all year or for varying periods of time during the year. National Historic Sites are related to historical events, National Grasslands are grass - dominated areas, and National Mountain Areas are mountainous regions. They are not primarily associated with water.

Answer:

National Wetland Areas