(a) A defense of lack of jurisdiction over the person, insufficiency of process or insufficiency of service of process is waived (1) if it is not included in a motion for joinder of defenses under Rule 10.7, or (2) if it is not made by motion, as provided in this Rule 10, nor included in a responsive pleading or in an amendment not requiring permission of the court, pursuant to that provided in Rule 13.1.
(b) The defense of failure to state a claim upon which relief can be granted, the defense of failure to join an indispensable party as provided in Rule 16, and the objection of failure to state a legal defense to a claim may be made in any pleading permitted or ordered under Rule 5.1, or by motion for judgment on the pleadings, or at the trial.
(c) Whenever it appears by suggestion of the parties or otherwise that the court lacks jurisdiction of the subject matter, the court shall dismiss the action.