Who heads up the department of justice under the executive branch?
a. secretary of state
b. secretary of justice
c. attorney general
d. secretary of commerce

The Department of Justice is a part of the Juidicial branch of the government - that is, dealing with Justice and courts. This already suggests that we can reject the options "Secretary of State" and "Secretary of Commerce" - those would rather be connected to the executuve branch. In fact, the correct answer is "Atorney General" - this is the name for the head of this Department. There is no position in the US with the name "Secretary of Justice" .