题目3单选题
图示结构中,A截面转角(设顺时针为正)为:( )<img src="https://tihai-oss-cloud.itihey.com/img/404178712a566e3fe3b0438997f0b4dc.png">A. <img src="https://tihai-oss-cloud.itihey.com/img/7286666a2ac01b9c4799efea90da835f.png">B. <img src="https://tihai-oss-cloud.itihey.com/img/c35fb6502b1e746aed77080f77502234.png">C. <img src="https://tihai-oss-cloud.itihey.com/img/1f9783dd774a157cf938ae3d37798f57.png">D. <img src="https://tihai-oss-cloud.itihey.com/img/9b1c0dad34c4298966cb0b45251b8083.png">