C i believe the answer is
Well a recent development would be new technology to be used
The Battle of the Alamo took place in 1836 at the Alamo in what is now San Antonio, Texas, At the time of the battle Texas belonged to Mexico so many people wanted to leave Mexico and to become a new country . Over 100 people tried out this plan including former Congressman Davy Crockett, but then an army of more than 13,000 Mexican soldiers arrived and surrounded the Alamo and attacked on March 6, 1836 . All of Texas' men died . ~I hope I helped .
To reduce air pollution because carbon emission harms the atmosphere.
Negative effective like killing most of them but positive because the natives taught them how to hunt and get warm for the upcoming winter but a lot of them fell sick
