An executive department whose main function is to promote safety is the Department of Justice. the Department of the Treasury. the Department of Commerce. the Department of the Interior.

Answer;

Department of Justice

Department of Justice is an executive department whose main function is to promote safety.

Explanation;

The purpose of the department of the justice is to enforce laws for the safety of American citizens. Other department give above undertake other roles;

The department of treasury is responsible for keeping track of money.

The department of commerce deals with businesses.

The department of the interior works to preserve America's natural land

The Department of justice is an executive department whose main function is to promote safety. The word "justice" already gives you an idea of what the answer is; D