城市道路植物配置树种选择的( )原则，是指分别选择适合当地立地条件的树种。A、A、适地适树B、B、科学C、C、因地制宜

单项选择题2. Additional validation studies on the SDIS are advised now that parent instructions have been expanded. Sleep specialists may have found a more valid and reliable method of measuring PLMD, and these specialists also have reached a broader consensus of the criteria for diagnosing OSAS. These validity studies should include larger sample sizes of all age ranges, especially older students, more Spanish-speaking participants, and larger samples of NARC-, DSPS-, and PLMD RLS-diagnosed cases.

单项选择题在教师表中查找“工龄”还没有输入数据的记录，使用的SQL语句是______ A、SELECT * FROM 教师表 WHERE 工龄 IS NULL B、SELECT * FROM 教师表 WHERE 工龄 IS .NULL. C、SELECT * FROM 教师表 WHERE 工龄=0 D、SELECT * FROM 教师表 WHERE 工龄=NULL