I would go with the 3rd option, but don't just count it yet. I'm 70% confident.
Answer:
A or C
Explanation:
HMS sounds like a military base
Answer:
Correct answer is D. to plan their annual agricultural activities.
Explanation:
D is the only correct option because they had to plan their crops rotations and as they were trading a lot with the outsiders and had to create a plan how this will function.
All other options are not correct as at the beginning none of these options were the reason why they used mathematics initially.
Damage to cities and farmland
