The new weapons of world war i, such as tanks, airplanes. flamethrowers, and poison gases, were supposed to

B is actually the only one that makes sense. It was all-out war, they wouldn't be concerned about trimming armies. There was no Geneva convention at the time, and they wouldn't ban new inventions in the middle of a war. And Germany didn't invent all these weapons.

But trench warfare was driving everyone mad with boredom and conditions were terrible. People were willing to try anything to break the stalemate.

The correct answer is a. when they started making tools that will them in cultivating lands, they could raise crops and that made them attached to one place for a longer period of time. after that, they started domesticating animals and building their own permanent settlements that resemble the ones we have today.