單項選擇題

圖示梁EI=常數(shù),B端的轉(zhuǎn)角是:()

A.5ql3/48EI(順時針)
B.5ql3/48EI(逆時針)
C.7ql3/48EI(逆時針)
D.9ql3/48EI(逆時針)