【名词&注释】
输尿管结石(ureteral calculi)、软坚散结(soften hard lumps and dispel nodes)、输尿管插管(catheterization of ureter)、平肝潜阳(soothing liver and anchoring yang)
[单选题]牡蛎煅用功效偏于
A. 平肝潜阳(soothing liver and anchoring yang) B. 软坚散结 C. 收敛固涩 D. 镇惊安神 E. 清肝明目