單項選擇題患者李某,男性,35歲,尿潴留,遵醫(yī)囑行留置導(dǎo)尿。導(dǎo)尿管插入尿道長度約為()

A.4~6cm
B.7~10cm
C.10~15cm
D.18~20cm
E.20~22cm