图示电路消耗电功率2W,则下列表达式中正确的是:()
A.(8+R)I2=2,(8+R)I=10 B.(8+R)I2=2,-(8+R)I=10 C.-(8+R)I2=2,-(8+R)I=10 D.-(8+R)I=10,(8+R)I=10