A.唐朝各族之间关系和睦
B.唐朝统治者放弃了对边疆用兵
C.唐朝统治者册封各族首领以固边防
D.唐朝实行比较开明的民族政策
Under a gold standard,countries may adopt excessively contractionary monetary policies as all scramble in vain for a larger share of the limited supply of world gold reserves.Can the same problem arise under a reserve currency standard when bonds denominated in different currencies are all perfect substitutes?
A.遣唐使来华
B.玄奘西游天竺
C.文成公主入藏
D.鉴真东渡日本