某施工单位与建设单位按《建设工程施工合同(示范文本)》签订了固定总价施工承包合同，合同工期390天，合同总价5 000万元。合同中约定按建标[2003]206号文综合单价法计价程序计价，其中间接费费率为20%，规费费率为5%，取费基数为人工费与机械费之和。

施工前施工单位向工程师提交了施工组织设计和施工进度计划(见下图)。

该工程在施工过程中出现了如下事件。

事件1：因地质勘探报告不详，出现图纸中未标明的地下障碍物，处理该障碍物导致工作A持续时间延长10天，增加人工费2万元、材料费4万元、机械费3万元。

事件2：结构施工阶段因建设单位提出工程变更，导致施工单位增加人工费4万元、材料费6万元、机械费5万元、工作E持续时间延长30天。

事件3：因施工期间钢材涨价而增加材料费7万元。

针对上述事件，施工单位按程序提出了工期索赔和费用索赔。

该工程的关键线路是（）。

A．①→②→④→⑥

B．①→③→⑤→⑥

C．①→②→⑤→⑥

D．①→②→③→⑤→⑥

Dina Borzekowski made a study of a group of third-grade students from six American schools. During a school year, nearly 400 students and their parents were asked to report on whether they had such things as televisions and computers in the home, as well as how often the child used them. The children’s language ability was tested (测验) twice over the year. Children who had a television set in the bedroom but did not have a computer at home scored (得分) the lowest, while students without TV in the bedroom but with a computer at home scored the highest. Students who had a television in the bedroom over the school year scored lower than those who had their TV taken away during the same time.
"This study suggests that taking TV sets out of children’s bedrooms, or not putting them there, may be helpful," said Borzekowski. "While this study does not prove (证明) that bedroom TV was the reason for the lower test scores, it suggests that children shouldn’t have TV in their bedrooms. It also suggests that a home computer may help a child’s test scores. The best way was having both: no TV in the bedroom and also a home computer to use. \

Who scored the highest on school tests
[A] Children with bedroom TV and home computers.
[B] Children without bedroom TV or home computers.
[C] Childern without bedroom TV but with home computers.