2. In the acute triangle $\triangle A B C$, condition Jia: “ $\mathrm{A}>\mathrm{B}>\mathrm{C}$ "; condition Yi: " $\sin 2 A<\sin 2 B<$ $\sin 2 C^{n}$ ", then Jia is Yi's ( ).
A. Sufficient but not necessary condition
B. Necessary but not sufficient condition
C. Sufficient and necessary condition
D. Neither sufficient nor necessary condition
2. $\mathrm{C}$

In an acute triangle $\triangle ABC$, if $A>B>C$, then $2A>2B>2C$. If $C \geqslant 45^{\circ}$, then $90^{\circ} \leqslant 2C < 90^{\circ}$. In this case, from $\sin 2A > 90^{\circ}$ we get $B > 90^{\circ} - C > 45^{\circ}$, hence $\sin 2B < \sin 2(90^{\circ} - C) = \sin 2C$, and thus $\sin 2A < \sin 2B < \sin 2C$. Conversely, in an acute triangle $\triangle ABC$, the above discussion can be reversed, and it is easy to see that condition A is also necessary.