Answer:
The Paris Peace Accords were signed on January 27, 1973
Explanation:
Colonial era: british
WW1: American
WW2: British (America for the atom bomb... but thats just one weapon. and they massed produced everything else really)
after that: AMERICA!!
I had a test with a question like this but we had options and I put answer D. Gunpowder. And it was right so idk about u