Final answer:
The not valid reason for filing a motion to dismiss is 'disagreement with the court's decision.' Valid reasons include lack of personal jurisdiction, failure to state a claim, or improper venue.
Step-by-step explanation:
The correct option is c) Disagreement with the court's decision. The reasons a, b, and d are considered valid reasons for filing a motion to dismiss. Lack of personal jurisdiction means the court does not have the legal authority over the person.
Failure to state a claim implies that even if the facts presented are true, there is no legal basis for a lawsuit. Improper venue suggests that the case is being heard in a location that is not appropriate under the legal rules that determine where a case may be heard.