Choose the correct answer. An intransitive verb completes an action without an object. A) It is true. B) It would be true if without were changed to with. C) It would be true if object were changed to indirect object. D) It would be true if intransitive were changed to transitive.

No. An intransitive verb does not need an object; the sentence makes complete sense once a subject and intransitive verb is properly used eg I walk is a complete sentence meaning I am in translational motion, going from place A to place B. If I wish to say something more I walk to the market, I walk to school. similarly I/You/He/She/It/They run. In the sentences in the examples please note that intransitive verb is followed by a preposition. A verb always denotes an action. Use of Intransitive verb does not mean that the action happens to the subject itself. I am not sure whether there are reflexive verbs to indicate that action is happening to the subject.

To answer the second part of your question, Yes the subject performs an action not necessarily to herself and an intransitive verb does not have an object.

But sometimes the intransitive verb may be used as a transitive verb, eg, I walk the dog

I trust I have made myself clear  

Explanation; using an intransitive verb mean the action happens to the subject itself or that the subject does the action but it doesn't need an object?

answer; ravenna,italy;

your answer would be d.)