Answer:
B. Atomic Weapons
Explanation:
Tanks were used near the end of WW1, with tanks such as the Renault FT, Mark 5, and the German A7Vs. Atomic weapons weren't even a concept back then. Gas was used since 1915, invented by a German scientist trying to develop a pesticide, and Machine guns such as the Vickers or MG08 were common in the trenches.
He became the Religious Leader of the Islamic Republic of Iran. After the revolution in which he worked to remove the Shah from Iran, he was named religious and political leader of Iran for life.
The French concentrated in exploring Canada because they already had forts in it in Quebec and in other parts of Canada, also there wasn't too much fighting over Canada except for the British so they decided to explore Canada.
I'm just quoting from a website
"the factors leading to the downfall of empires of Ghana, Mali, and Songhai
Climate change and struggles with Berber groups in the Sahara led to the downfall of the Ghanaian Kingdom
Later kings followed the patrilineal tradition, where the eldest son succeeds the father. Since there seems to have been no strict tradition, there were many fights over succession. This led to civil wars and was a large part of the reason why the Mali Empire declined.
Like the Mali Empire, the Songhai Empire also suffered from many battles over succession. In Songhai, the brothers of the king often tried to depose him; in turn, some kings tried to protect themselves by killing all their brothers. The last great battle for succession occurred when a great army general challenged a new king. Many men were killed in the battle for control of the country and the Songhai army was weakened. When troops from Morocco invaded to seize control of and revive the trans-Saharan trade in gold, the Songhai Empire could not win and was conquered, making this the last of the great West African empires."
