Identify this kind of argument: If naturalism is true, then all things are determined and there is no free will. If there is no free will then morality makes no sense. Therefore, if naturalism is true then morality makes no sense.

Deductive argument

Explanation:

A deductive argument is argument that reaches conclusion based on the assumption that premise is true. It is the direct opposite of inductive argument(also called inductive reasoning) whereby a conclusion is reached based on premise without assumed truth(as in one specific instance of a thing).

From the above example, we see deductive argument as we conclude(last sentence) based on assumed truths from preceding sentences(premise)