Since he started high school, he’s come to school by bike_____.     [ ]

A. on his own  

B. by his own    

C. in his own    

D. with his own

下列选项中，不属于《住宅质量保证书》中的内容是( )。

A．工程质量监督部门核验的质量等级
B．地基基础和主体结构在合理使用寿命年限内承担保修
C．配电负荷
D．用户报修单位答复和处理的时限