下列关于生物技术安全性和伦理问题的阐述中，正确的是（ ）
A：目前克隆技术尚难克服重构胚胎成功率低、流产率高、胎儿畸形率高等问题
B：治疗性克隆和生殖性克隆研究层次不一样，前者是细胞或器官水平、后者是个体水平
C：试管婴儿和设计试管婴儿在技术和实践层面上都可以解决不孕症者的生育问题
D：不考虑基因歧视问题，通过基因检测有助于对某些疾病及早采取预防措施
A．信息归纳
阅读短文内容。根据所提供的信息，完成信息卡内容。
I am Lily，a student in Beijing．I am fifteen years old．My birthday is on July 6th．I like volleyball very much．I play volleyball with my friends after school．My mother is 42 years old．Her birthday is in June．She is an English teacher in a middle school．My father is 45 years old．His birthday is in October．He likes playing basketball．He can play it very well．
Bill is my pen friend from the US．He is sixteen years old．His birthday is on March 8th．He likes Soccer and baseball．He likes ice-cream very much．He eats it every day．Bill always helps me with my English．I like him very much．
Information Card
When is Lily's birthday?
Her birthday is on ____．
How old is Lily's mother?
She is ____years old．
What sports does Lily's father like?
He likes ____．
Who is Bill?
He is Lily's ____．
What food does Bill like?
设等差数列{an}的前n项和为Sn，且S4=4S2，a2n=2an+1．求数列{an}的通项公式.
