Answer:
World War I changed the way wars were fought because of the widely known trench warfare. Because troops inside the trenches were much more protected than troops outside, it led to much more prolonged battles.
Sorry, what do u mean by branch?
I have to say B. The rest were concepts made in Greece, by Greek philosophers, politicians, or mathematicians. An example for an advancement in math is the Pythagorean Theorem. I hope this helps!
It’s c is the right answer
