State the impossibility trinity (fixed exchange rates, independent monetary policy, and international capital mobility)

[answerhappygod]

State the impossibility trinity (fixed exchange rates,
independent monetary policy, and international capital mobility) as
a fundamental proposition in international finance. Use it to
describe the situations in Mainland China, Hong Kong, and the U.S.
Especially in China for now, its capital controls (the opposite of
capital mobility) are increasingly leaky and its “fixed” (or
managed “floating”) exchange rate regime is increasingly shaky
under the constant U.S. pressure for RMB appreciations, how about
China’s monetary autonomy?