设 △ABC\bigtriangleup {ABC}△ABC 内角 A,B,CA,B,CA,B,C 的对边分别为 a,b,ca,b,ca,b,c . 若 sinA=cosB=tanC\sin A = \cos B = \tan CsinA=cosB=tanC , 则下列说法正确的是( )A. A+B=π2A + B = \frac{\pi }{2}A+B=2π B. 2A+C=3π2{2A} + C = \frac{3\pi }{2}2A+C=23π C. a>ba > ba>b D. c>bc > bc>b