A. $u_{\rm {GS}}$大于$U_{\rm {GS}(off)}$并且$u_{\rm {GD}}$小于$U_{\rm {GS}(off)}$
B. $u_{\rm {GS}}$大于$U_{\rm {GS}(off)}$并且$u_{\rm {GD}}$大于$U_{\rm {GS}(off)}$
C. $u_{\rm {GS}}$小于$U_{\rm {GS}(off)}$并且$u_{\rm {GD}}$大于$U_{\rm {GS}(off)}$
D. $u_{\rm {GS}}$小于$U_{\rm {GS}(off)}$并且$u_{\rm {GD}}$小于$U_{\rm {GS}(off)}$