Which boolean operator combines two map layers by getting areas common to both layers?

• A. OR
• B. NOT
• C. AND
• D. XOR

Answer: (C)

Combining two map layers to keep only the areas present in both uses the logical AND operation. In boolean logic, AND is true only when both inputs are true, so when you apply it to map layers, you get a new layer that shows locations where both input layers indicate the feature exists. This is the intersection of the layers. For example, if one layer marks forested areas and another marks zones with high soil moisture, an AND operation will highlight only the areas that are both forested and have that moisture condition.

This differs from OR, which expands to include areas where either layer indicates the feature (the union); NOT, which inverts a layer; and XOR, which keeps only areas that are in exactly one layer, not both. Because the goal is to find areas common to both layers, the AND operator is the best choice.