China
india only win
no china has much more men
Most likely India they have a stronger army
No one would win especially if either of them uses nuclear weapons. The whole world will lose.
Without either side using their nuclear weapons, and with the Indian Army resisting a Chinese Army invasion, I think India would have a good chance of winning. If it were the other way around China would win, but India would have little reason to invade China.
There is two China's the PRC and the Republic of China that's why it was a civil war so I guess its because no matter who won China would still win.
INDIA
The US and China are not at war so this question is unanswerable.
China
china
It is likely that US might win the war. Russia could defeat both India and China together, but they would get a lot of their soldiers lost in the battle. US has much better weapons and better, trained soldiers than Russia, making it more powerful.