The answer you are looking for is option B I hope this helps you.
they worled for reform and social services
The Tang Dynasty of China when faced with rebellion from General An Lushan in their northern territories sought outside support from mercenary forces. This was done a number of times during the rebellion, these mercenaries were typically Arab, however, we also have examples of soldiers brought from Uighur to fight with the Tang and numbered in the thousands in the fight against Lushan's forces.
With the help of mercenary forces, the Tang were able to take back several important capital cities of China and effectively eliminated the rebellion of Lushan, as well as his later supporters and successors.
It’s the passage of the indian removal act i took the test
He invented the Bolometer. An instrument capable of detecting minute differences in temperature
