Question

what material is strip mining mainly used to extract?
salt and limestone
coal
gold and silver
iron and copper

Explanation:

Strip mining is a surface mining method. Coal is one of the main materials extracted by strip mining. It is relatively easier to access coal seams near the surface using this method. While salt, limestone, gold, silver, iron, and copper can also be mined, strip mining is most commonly associated with coal extraction.

Answer:

B. coal