【单选题】
一质量为m的均质杆长为l,绕铅直轴OO’成角θ转动,其转动惯量为()<br /> <img src="https://nimg.ppkao.com/2019-04/wuacheng/2019042917135495558.jpg?sign=d2999171f64b62a86a1d411c5566d74b&t=62d5ba83" /><br /> <img src="https://nimg.ppkao.com/2019-04/wuacheng/2019042917140846243.jpg?sign=98b426dfb09db1eebea9aaa3de3bb91e&t=62d5ba83" />
A、A
B、B
C、C
D、D