Answer: Military Endeavors.
Step-by-step explanation:
As mentioned above, the word Mars is the name of the Roman god of war. If we were to use the word Martial with this relation in mind, it means that it would have to be something related to war.
The only option related to war is "Military Endeavors" so this would be the best option. For instance, if it is said that "troops are being martialed" it means that soldiers are being called up to fight or if a place is under Martial law then it means that the place is under military type rule at that moment.