题目1单选题
若某单位负反馈控制系统的开环传递函数为<img src="https://tihai-oss-cloud.itihey.com/img/7b6e0018519317b0bcf7d02a2a6c226f.png">,则该系统的特征方程为 ( )A. <img src="https://tihai-oss-cloud.itihey.com/img/8407ee8e4e9545fc7df61c38c6235258.png">B. <img src="https://tihai-oss-cloud.itihey.com/img/1c1f60257b6eae3e70abe49e18a7c8b5.png">C. <img src="https://tihai-oss-cloud.itihey.com/img/fcdf3e08eb70c7844a911be1b94b5fea.png">D. <img src="https://tihai-oss-cloud.itihey.com/img/f527d13cb0a95c0da2a68836798a8604.png">