翻译:他在当地中学接受教育,此后他接着上了北京大学.
1.两句之间没有并列连词and等连接,说明逗号后面是一个非限制性定语从句.
由此可以排除BD,楼主要知道that是不能作为非限制性定语从句的先行词的.
2.此处which指的是He was educated at the local high school整个主句,在定语从句中做after的宾语,即:
(after which) he went on to Beijing University
= (after he was educated at the local high school) he went on to Beijing University.